掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry - A European Journal  

Zinc carboxylate complexes are widely utilized as artificial models of metalloenzymes and as secondary building units of PCPs/MOFs. However, the relationship between the structure of the monodentate carboxylato ligand and the molecular arrangement of multinuclear zinc carboxylate complexes is not fully understood because of the coordination flexibility of the Zn ion and carboxylato ligands. Herein, we report the structural analysis of a series of complexes derived from zinc (meth)acrylate which has a linear infinite chain structure. The molecular structure of μ4-oxido-bridged tetranuclear complexes [Zn4(μ4-O)(OCOR)6] revealed a distorted Zn4O core. Crystallization of zinc acrylate under aqueous conditions afforded a μ3-hydroxido-containing pentanuclear complex [Zn5(μ3-OH)2(OCOR)8] as the repeating unit of an infinite sheet-like structure in the solid state. It was also obtained by the hydrolysis of the μ4-oxido-bridged tetranuclear complex. In sharp contrast, the methacrylate analog retained the methacrylato ligands under aqueous crystallization conditions to form a macrocyclic dodecanuclear complex with methacrylato as the sole ligand.

DOI： 10.1002/chem.202400586

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Nature Reviews Chemistry  

The reactivity of carbonyl functional groups largely depends on the substituents on the carbon atom. Reversal of the commonly accepted order of reactivity of different carbonyl compounds requires novel synthetic approaches. Achieving selective reduction will enable the transformation of carbon resources such as plastic waste, carbon dioxide and biomass into valuable chemicals. In this Review, we explore the reduction of less reactive carbonyl groups in the presence of those typically considered more reactive. We discuss reductions, including the controlled reduction of ureas, amides and esters to aldehydes, as well as chemoselective reductions of carbonyl groups, including the reduction of ureas over carbamates, amides and esters; the reduction of amides over esters, ketones and aldehydes; and the reduction of ketones over aldehydes. (Figure presented.)

DOI： 10.1038/s41570-024-00608-z

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DOI： 10.26434/chemrxiv-2024-69jc4

掲載種別：研究論文（学術雑誌）   出版者・発行元：Organometallics  

Hydrogenolysis of less reactive carbonyl compounds such as urethanes and ureas is a challenging but promising transformation to utilize new chemical feedstocks, such as plastic waste and carbon dioxide fixation products. In these transformations, pincer-type complexes consisting of Ru and Mn have been intensively investigated but catalyst design with bidentate ligand systems has rarely been explored. We report here the synthesis of a Mn complex supported by a PN bidentate ligand consisting of phosphino and pyrrolido coordination sites, the molecular structure of which has been fully characterized. The Mn complex catalyzed the hydrogenolysis of urethanes and ureas. In the case of the hydrogenolysis of 1,3-diphenylurea, formanilide was obtained as a product. In addition, the present Mn complex did not promote the hydrogenation of carboxamides, showing a unique reactivity that preferentially reduces urethanes and ureas over carboxamides, in contrast to the general reactivity order of carbonyl compounds.

DOI： 10.1021/acs.organomet.4c00032

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掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/tcr.202380901

掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemical Record  

Carbon-fluorine bonds are stable and have demonstrated sluggishness against various chemical manipulations. However, selective transformations of C−F bonds can be achieved by developing appropriate conditions as useful synthetic methods in organic chemistry. This review focuses on C−C bond formation at monofluorinated sp3-hybridized carbons via C−F bond cleavage, including cross-coupling and multi-component coupling reactions. The C−F bond cleavage mechanisms on the sp3-hybridized carbon centers can be primarily categorized into three types: Lewis acids promoted F atom elimination to generate carbocation intermediates; nucleophilic substitution with metal or carbon nucleophiles supported by the activation of C−F bonds by coordination of Lewis acids; and the cleavage of C−F bonds via a single electron transfer. The characteristic features of alkyl fluorides, in comparison with other (pseudo)halides as promising electrophilic coupling counterparts, are also discussed.

DOI： 10.1002/tcr.202300033

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出版者・発行元：Polymer  

Here, we report copolymerization of ethylene or propylene with norbornenes functionalized with polar groups, using palladium catalysts, Pd/IzQO, Pd/BPMO, or Pd/PS. In this study, the structural analyses for copolymers of ethylene with methyl 5-norbornene-2-carboxylate (E/MeNBE), tert-butyl 5-norbornene-2-carboxylate (E/tBuNBE), or 5-norbornene-2-carboxylic acid (E/NBA) were conducted. Also, this work serves as the first example of coordination–insertion copolymerization of propylene with disubstituted polar olefins. In addition, the thermal properties of the obtained copolymers were evaluated by the DSC analyses.

DOI： 10.1016/j.polymer.2023.126116

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DOI： 10.26434/chemrxiv-2023-z49zw

掲載種別：研究論文（学術雑誌）   出版者・発行元：Macromolecules  

Active methylene compounds, such as nitrile compounds 2 and carbonyl compounds 4, acted as chain transfer agents (CTAs) for the alternating copolymerization of CO2 and cyclohexene oxide (CHO) in the presence of tetranuclear macrocyclic complex 1 to give end-functionalized polycarbonates with a narrow molecular weight distribution (1.15-1.45) and high carbonate linkage (>95%). The amounts of these CTAs directly controlled the Mn of the resulting polycarbonate. Based on the mechanistic studies, we propose that the initiation step of the alternating copolymerization was the production of the corresponding alcohols 3 or 5 by reactions of 2 or 4 with CHO, respectively, through the deprotonation of a methylene proton of 2 or 4 by the catalyst. Furthermore, highly acidic nitrile compounds, such as malononitrile (2i) and (p-tolylsulfonyl)acetonitrile (2j), resulted in double chain propagation to give the corresponding telechelic polycarbonate diols.

DOI： 10.1021/acs.macromol.2c01761

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掲載種別：研究論文（学術雑誌）   出版者・発行元：American Chemical Society ({ACS})  

A mechanistic study of the Rh-catalyzed cross-coupling reaction of vinylic ethers with aryl Grignard reagents via C(sp2)-O bond cleavage is reported herein. To obtain mechanistic insights, the reaction was conducted in a flow reactor, and kinetic studies revealed that the reaction obeyed first-order and zeroth-order kinetics, with respect to vinyl ether and aryl Grignard reagents, respectively. The olefinic ligands in the Rh precatalysts significantly affected the catalytic performance, and the catalytic activity of [RhCl(CH2=CH2)2]2 was ca. 110 times higher than that of [RhCl(cod)]2. Furthermore, the kinetic studies revealed that bidentate ancillary ligand, COD, forms a dormant species to decelerate the catalytic turnover. Computational studies suggested that the reaction between diarylrhodate, generated by the reaction of a Rh precatalyst with two molecules of aryl Grignard reagents, and vinylic ethers proceeded through Mg cation-assisted insertion/anti-β-oxygen elimination rather than oxidative addition/reductive elimination and nucleophilic substitution at the vinylic carbon (SN2 V). In the transition state, the Mg countercation was coordinated to the ethereal oxygen atom in the substrate and facilitated not only C-O bond cleavage but also the insertion of the C=C bond into the Rh-Ph bond. These strategies and mechanistic insights were successfully applied to develop a strategy for the Rh-catalyzed cross-coupling reaction of fused vinylic ethers, benzofurans, and aryl Grignard reagents, wherein the bond cleavage occurred selectively at the vinylic C(sp2)-O bond, even in the presence of Ar-O, Ar-Cl, or Ar-Br bonds. These results demonstrated the unique chemoselectivity of the present Rh-catalyzed reaction, which will allow the development of a complementary synthetic approach to the existing Ni-catalyzed cross-coupling reaction via C-O bond cleavage.

DOI： 10.1021/acscatal.2c01974

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Organic and Biomolecular Chemistry  

Transition-metal catalysts are powerful tools for carbon-carbon bond-forming reactions that are difficult to achieve using native enzymes. Enzymes that exhibit inherent selectivities and reactivities through host-guest interactions have inspired widespread interest in incorporating enzymatic behavior into transition-metal catalytic systems that highly efficiently produce enantiopure compounds. Nevertheless, bio-inspired transition-metal catalysts that are highly enantioselective and reactive have rarely been reported. In this study, we applied γ-cyclodextrin-imidazolium salts to the rhodium-catalyzed asymmetric arylations of aldehydes. The method exhibits wide substrate scope and the corresponding arylcarbinols are obtained in excellent yields under optimized conditions, with enantiomeric excesses of up to 96% observed. Kinetic and competition experiments revealed that self-inclusion of the Rh complex contributes to the high enantioselectivity and reactivity achieved by this catalytic system. Thus, this bio-inspired self-inclusion strategy is promising for the development of highly enantioselective and reactive transition-metal catalysts for asymmetric carbon-carbon bond formation. This journal is

DOI： 10.1039/D1OB02014E

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PubMed

掲載種別：研究論文（学術雑誌）   出版者・発行元：American Chemical Society ({ACS})  

Anionic homoleptic organo-Transition metal complexes can be prepared from organolithium reagents and transition metal salts and are key reactive intermediates in C-C bond formation. However, the interaction between the anionic component and cationic counterparts of multianionic homoleptic organo-Transition metal complexes in solution remains unclear, unlike well-studied monoanionic complexes such as organocuprates. Here we have prepared and structurally characterized lithium hexaphenylrhodate(III) and-iridate(III) complexes, [Li(12-crown-4)2][MPh6{Li(thf)}2] (M = Rh and Ir), as the first examples of hexaaryl complexes of d6 metals. In the crystals, two Li cations contact the trianionic MPh6 moiety, while the other exists as a solvent-separated ion pair. In THF, hexaphenylrhodate decomposed within 1 h. In contrast, the Ir analog was stable. 7Li NMR and X-ray absorption fine structure analysis revealed the solution-phase structure of hexaphenyliridate, which maintained a partially contacted ion pair structure even in THF, a coordinating solvent.

DOI： 10.1021/acs.organomet.1c00248

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Royal Society of Chemistry ({RSC})  

A simple and efficient methodology for the synthesis of 2-aryl-perfluorobenzoxazoles was developedviaa direct dual C-F functionalization of perfluorobenzene with arylformamide in the presence of a Fe(ii)/NaH/DMSO system. Various substituted aryl formamides are tolerated giving good yields. The preliminary fluorescence properties (up to 99% fluorescence quantum yield of3d) of the products and their applications in the synthesis of uniform cubic platinum nanoparticles indicate that these perfluorobenzoxazole derivatives may have certain potential applications in materials chemistry.

DOI： 10.1039/D1TC03338G

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Royal Society of Chemistry ({RSC})  

3,5-Dimethylpyrazole (Pz*H) in well-defined Cp*RhIII(Cp* = 1,2,3,4,5-pentamethylcyclopentadienyl) complexes, or as an additive to [Cp*RhCl2]2enhances catalytic activity in the dehydrogenation of dimethylamine-borane (DMAB) at room-temperature. Mechanistic studies indicate that the Lewis acidic RhIII-centre and dangling N-atom of the Pz* fragment operate cooperatively in accepting a hydride and proton from DMAB, respectively, leading directly to dimethylamino-borane and a RhIII-H complex. The rate limiting step involves protonation of the RhIII-H by the proximal NH fragment of the Pz*H moiety.

DOI： 10.1039/D1DT01705E

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掲載種別：研究論文（学術雑誌）   出版者・発行元：American Chemical Society ({ACS})  

Lithium diphenyliridate complexes bearing cycloocta-1,5-diene (COD) as a ligand were synthesized by treating [IrCl(cod)]2 with phenyllithium and subsequent recrystallization. X-ray crystallographic analysis of the complexes showed both contact ion pair and solvent-separated ion pair structures depending on the coordination environment around the Li cation. Natural bond orbital analysis revealed that the anionic charge formally described on Ir efficiently delocalizes to not only the phenyl moieties but also the COD ligand. This result contrasts to the rhodium-analogues, where the anionic charge is more localized at the metal center, suggesting stronger back-donation from Ir to ligands than that of Rh.

DOI： 10.1021/acs.organomet.0c00446

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：American Chemical Society ({ACS})  

Heteromultimetallic complexes consisting of three Co(II) ions and one lanthanide ion were synthesized and applied to the alternating copolymerization of CO2 and cyclohexene oxide. Unlike the conventional cobalt(III) salen complexes, the high thermal stability of the present catalyst allowed us to reach a turnover number of 13000, one of the highest values ever reported for multimetallic systems. The chain propagation was first-order to the catalyst, suggesting a cooperative behavior of the metal centers.

DOI： 10.1021/acs.inorgchem.0c01156

Web of Science

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Wiley  

Changes in the photophysical properties of pyrene (Py)-octafluoronaphthalene (OFN) co-crystals (Py⋅OFN) upon mechanical stimuli are described herein. The Py⋅OFN co-crystal showed a mechano-induced bathochromic shift in emission, and a similar tendency was observed for the 1,3,6,8-tetramethylpyrene-OFN co-crystal. These shifts are due to disruption of the microscopic molecular orientation in the co-crystal, which allows for excimer formation. In sharp contrast to the parent Py⋅OFN and methyl-substituted Py-OFN co-crystals, no mechano-induced bathochromic shift was observed when longer alkyl chains were introduced to the 1-, 3-, 6-, and 8-positions of the Py chromophore. This photophysical opposability against mechanical stimuli could be explained by the orthogonally oriented alkyl groups on the Py ring, which existed between two Py cores like pillars. This fixed OFN to maintain the face-to-face alternatively stacked structure of the co-crystal and thus prevented the formation of the Py excimer. The pillar effect demonstrated herein provides a rational design for co-crystalline systems that are photophysically stable against mechanical stresses.

DOI： 10.1002/asia.202000138

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PubMed

掲載種別：研究論文（学術雑誌）   出版者・発行元：American Chemical Society ({ACS})  

Copper-catalyzed oxidative intramolecular cyclization of o-alkylated anilines via cleavage of C(sp3)-H and N-H bonds for the production of indolines is described. This approach provides a straightforward strategy for the synthesis of nitrogen-containing heterocyclic compounds through the functionalization of unactivated C(sp3)-H bonds with high site selectivity. The present catalytic system shows high preference for functionalization of unactivated C(sp3)-H bonds over C(sp2)-H bonds, leading to C-N bond formation.

DOI： 10.1021/acs.joc.9b02404

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出版者・発行元：Yuki Gosei Kagaku Kyokaishi/Journal of Synthetic Organic Chemistry  

Owing to their extremely high bond dissociation energies, carbon-fluorine bonds find limited usage in synthetic organic chemistry In this context, we investigated novel catalytic carbon-carbon bond forming reactions using alkyl fluorides as electrophiles. As a strategy for realizing the carbon-fluorine bond cleavage, we focused on ate complexes consisting of a highly nucleophilic transition metal anion and a Lewis acidic counter cation. The carbon-fluorine bond in alkyl fluorides is activated by the coordination of fluorine atom to the counter cation, enabling nucleophilic attack from anionic transition metal center or its own ligand. This novel methodology of catalytic conversion of carbon-fluorine bonds to carbon-carbon fragments provides a new synthetic strategy complimentary to traditional transformations.

DOI： 10.5059/yukigoseikyokaishi.78.109

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出版者・発行元：Journal of the Japan Petroleum Institute  

The functionalization of 1,3-butadiene with carbon electrophiles was investigated using homogeneous transition metal catalysts. A copper catalyst generated by treatment of Cu salt with alkyl Grignard reagent catalyzed internal carbon selective reductive alkylation of 1,3-butadiene with alkyl fluoride as a carbon electrophile and the alkyl Grignard reagent as a hydride source. Nickel promoted dimerization and alkylarylation of 1,3-butadiene with the same substrates combination. The application of polyfluoroarenes as carbon electrophiles led to similar transformations to achieve the functionalization of 1,3-butadiene. The substrate scope and details of the reaction mechanism of these transformations are provided.

DOI： 10.1627/JPI.63.123

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Wiley  

DOI： 10.1002/chem.201904002

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Wiley  

The relationship between the photophysical properties and molecular orientation of 1,3,6,8-tetraalkylpyrenes in the solid state is described herein. The introduction of alkyl groups with different chain structures (in terms of length and branching) did not affect the photophysical properties in solution, but significantly shifted the emission wavelengths and fluorescence quantum yields in the solid state for some samples. Pyrenes bearing ethyl, isobutyl, or neopentyl groups at the 1-, 3-, 6-, and 8-positions showed similar emission profiles in both the solution and solid states. In contrast, pyrenes bearing other alkyl groups exhibited an excimer emission in the solid state, similar to that of the parent pyrene. On studying the photophysical properties in the solid state with respect to the obtained crystal structures, the observed solid-state photophysical properties were found to depend on the relative position of the pyrene chromophores. The solid-state photophysical properties can be controlled by the alkyl groups, which provide changing crystal packing. Among the pyrenes tested, 1,3,6,8-tetraethylpyrene showed the highest fluorescence quantum yield of 0.88 in the solid state.

DOI： 10.1002/chem.201903224

Web of Science

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Wiley  

We report herein a Rh(III)-catalyzed oxidative coupling reaction of 2-phenylpyridine derivatives with arylsilane reagents. In this reaction, AgF plays important roles as both oxidant and C−Si bond activator. Addition of the catalytic amount of pivalic acid was found to be the key to achieve high yields of the desired products in short reaction times.

DOI： 10.1002/ajoc.201900362

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掲載種別：研究論文（学術雑誌）   出版者・発行元：American Chemical Society ({ACS})  

Oxidative dimerization of 1,3-dienes on Ni(0) is one of the most fundamental elemental processes; however, the molecular structure of the key intermediate, Ni(C8H12)(L), arising from 1,3-butadiene had not yet been defined. We first identified the detailed structure of Ni(C8H12)(L) (L = PCy3) by X-ray crystallography and revealed that the C8 moiety was bound to Ni in an η1:η3 fashion with a cis-C-C double bond of the σ-allyl group located in the same face with the central carbon of the π-allyl group. In addition, the formation of the corresponding anionic complexes upon treatment with organometallic reagents was confirmed by NMR.

DOI： 10.1021/acs.organomet.9b00296

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掲載種別：研究論文（学術雑誌）   出版者・発行元：American Chemical Society ({ACS})  

A nickel-catalyzed three-component coupling reaction between perfluoroarenes and two molecules of a 1,3-diene in the presence of an alkyl Grignard reagent, which acted as a hydride source, provided 3-perfluoroarylated-1,7-octadienes via 1,3-diene dimerization and subsequent perfluoroarylation upon C-F bond cleavage. The reaction proceeded smoothly in a regioselective manner by simply combining NiCl2 and PPh3 as a catalyst and tolerated various functional groups on the perfluoroarenes. When substituted perfluoroarenes were employed, the reaction selectively occurred at the para-position. Mechanistic studies revealed that an anionic Ni complex, generated upon the reaction of Ni(0) with two molecules of a 1,3-diene and an alkyl Grignard reagent, played an important role in the C-C bond forming step with perfluoroarenes. The C-F bond cleavage was found to be a relatively fast step in the catalytic cycle.

DOI： 10.1021/acs.joc.8b01266

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry Letters  

Iron-catalyzed cross-coupling reaction of alkyl halides with alkyl Grignard reagents by the combined use of cyclopentadienyl ligand and 1,3-butadiene additive is described. The reaction smoothly proceeds at room temperature using unactivated alkyl bromides and fluorides via non-radical mechanism, which is in sharp contrast with hitherto known Fe-catalyzed cross-coupling reactions of alkyl halides.

DOI： 10.1246/cl.180201

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Royal Society of Chemistry ({RSC})  

We describe the mechanism, substituent effects, and origins of the selectivity of the nickel-catalyzed four-component coupling reactions of alkyl fluorides, aryl Grignard reagents, and two molecules of 1,3-butadiene that affords a 1,6-octadiene carbon framework bearing alkyl and aryl groups at the 3- and 8-positions, respectively, and the competing cross-coupling reaction. Both the four-component coupling reaction and the cross-coupling reaction are triggered by the formation of anionic nickel complexes, which are generated by the oxidative dimerization of two molecules of 1,3-butadiene on Ni(0) and the subsequent complexation with the aryl Grignard reagents. The C-C bond formation of the alkyl fluorides with the γ-carbon of the anionic nickel complexes leads to the four-component coupling product, whereas the cross-coupling product is yielded via nucleophilic attack of the Ni center toward the alkyl fluorides. These steps are found to be the rate-determining and selectivity-determining steps of the whole catalytic cycle, in which the C-F bond of the alkyl fluorides is activated by the Mg cation rather than a Li or Zn cation. ortho-Substituents of the aryl Grignard reagents suppressed the cross-coupling reaction leading to the selective formation of the four-component products. Such steric effects of the ortho-substituents were clearly demonstrated by crystal structure characterizations of ate complexes and DFT calculations. The electronic effects of the para-substituent of the aryl Grignard reagents on both the selectivity and reaction rates are thoroughly discussed. The present mechanistic study offers new insight into anionic complexes, which are proposed as the key intermediates in catalytic transformations even though detailed mechanisms are not established in many cases, and demonstrates their synthetic utility as promising intermediates for C-C bond forming reactions, providing useful information for developing efficient and straightforward multicomponent reactions.

DOI： 10.1039/C7SC04675H

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Advanced Synthesis and Catalysis  

An iterative Ni-catalyzed C(sp3)−C(sp3) cross-coupling reaction of a novel cis-cyclopropane containing bifunctional building blocks with alkyl halides and alkyl Grignard reagents enabled the introduction of a cyclopropane ring into the desired position(s) of saturated carbon frameworks, providing a straightforward synthetic route to cyclopropane fatty acids. The present method creates a direct route for the construction of saturated carbon frameworks, and can avoid the tedious multistep operations based on unsaturated functional group manipulations that are often employed in conventional synthetic routes. This method could be applicable to the synthesis of trans-cyclopropane fatty acids and enantioenriched cyclopropane fatty acids. Formal synthesis of α-mycolic acid was achieved by the C(sp3)−C(sp3) cross-coupling reaction of cyclopropane-containing bifunctional building blocks. (Figure presented.).

DOI： 10.1002/adsc.201800901

Web of Science

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Heterocycles  

Cyclodextrin (CD) homo and hetero dimers including an imidazolium salt were prepared from imidazolyl CDs and the corresponding CD monotosylates. The CD dimer imidazolium salts were characterized by MALDI-TOF mass and NMR spectroscopies.

DOI： 10.3987/COM-18-13993

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry Letters  

Copper complexes, generated by the treatment of CuCl2 with EtMgCl, catalyze a reductive coupling reaction of perfluoro-arenes with 1, 3-dienes via C-F bond cleavage, in which the internal carbon of 1, 3-dienes preferably reacts with perfluoro-arenes giving rise to branched allylated perfluoroarenes as a major coupling product.

DOI： 10.1246/cl.170650

Web of Science

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：American Chemical Society ({ACS})  

The cross-coupling reaction of unactivated alkyl fluorides with alkyl Grignard reagents by a CoCl2/LiI/1,3-pentadiene catalytic system is described. The present reaction smoothly cleaved C-F bonds under mild conditions and achieved alkyl-alkyl cross-coupling even when sterically hindered tertiary alkyl Grignard reagents were employed. Since alkyl fluorides are inert toward many reagents and catalytic intermediates, the use of the present reaction enables a new multistep synthetic route to construct carbon frameworks by combining conventional transformations.

DOI： 10.1021/acs.orglett.7b01370

Web of Science

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：American Chemical Society ({ACS})  

The Iodine-mediated oxidative intramolecular amination of anilines via cleavage of unactivated (sp3)C-H and N-H bonds for the production of indolines is described. This transition-metal-free approach provides a straightforward strategy for producing (sp3)C-N bonds for use in the preferential functionalization of unactivated (sp3)C-H bonds over (sp2)C-H bonds. The reaction could be performed on a gram scale for the synthesis of functionalized indolines.

DOI： 10.1021/acs.orglett.7b00846

Web of Science

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Heterocycles  

Cyclic nigerosyl-(1→6)-nigerose (CNN) monotosylate 1 and CNN ditosylate 2 were prepared and characterized by MALDI-TOF mass and NMR Spectroscopies. CNN bis-imidazolium salts 3 were also obtained by nucleophilic displacement reaction of 2 with imidazoles.

DOI： 10.3987/COM-16-S(S)69

Web of Science

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Royal Society of Chemistry ({RSC})  

A Ni-catalyzed oxidative C-H/C-H cross-dehydrogenative coupling (CDC) reaction was developed for constructing various highly functionalized alkyl (aryl)-substituted thiophenes. This method employs thiophenes and aliphatic (aromatic) amides that contain an 8-aminoquinoline as a removable directing group in the presence of a silver oxidant. The approach enables the facile one-step synthesis of substituted thiophenes with high functional group compatibility via double C-H bond cleavage without affecting C-Br and C-I bonds. DFT calculations verify the importance of KH2PO4 as an additive for promoting C-H bond cleavage and support the involvement of a Ni(iii) species in the reaction.

DOI： 10.1039/C7CC04252C

Web of Science

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry - An Asian Journal  

Iron-catalyzed cross-coupling reaction of vinylic ethers with aryl Grignard reagents is described. The reaction proceeded at room temperature with catalytic amounts of an iron salt without the aid of costly ligands and additives. In this catalytic system, vinylic C−O bonds were preferentially cleaved over aromatic C−O bonds of aryl ethers or aryl sulfonates.

DOI： 10.1002/asia.201600972

Web of Science

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Organic Letters  

An anionic Ni complex was isolated and its structure determined by X-ray crystallography. With such an anionic complex as a key intermediate, a regio- and stereoselective multicomponent coupling reaction of perfluoroarenes, aryl Grignard reagents, and 1,3-butadiene in a 1:1:2 ratio was achieved, resulting in the formation of 1,6-octadiene derivatives containing two aryl groups, one from the perfluoroarene and the other from the aryl Grignard reagent, at the 3- and 8-positions, respectively.

DOI： 10.1021/acs.orglett.6b02343

Web of Science

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Wiley  

DOI： 10.1002/anie.201602431

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Wiley  

In the presence of a nickel catalyst, 1,3-butadiene undergoes selective dimerization and alkylarylation with alkyl fluorides and aryl Grignard reagents to give 1,6-octadienes with alkyl and aryl groups at the 3- and 8-positions, respectively, by the consecutive formation of three carbon-carbon bonds. The formation of an anionic nickel complex plays an important role in forming C-C bonds with alkyl fluorides.

DOI： 10.1002/anie.201601126

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Wiley  

DOI： 10.1002/ange.201601126

掲載種別：研究論文（学術雑誌）   出版者・発行元：Wiley  

DOI： 10.1002/ange.201602431

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Organic and Biomolecular Chemistry  

A regioselective phosphorylation method for myo-inositol was developed by utilizing readily preparable BINOL-derived phosphoramidites. The method also facilitated the complete separation of the diastereomeric products by simple chromatography. Based on this phosphorylation and Ni-catalyzed alkyl-alkyl cross-coupling reaction for long fatty acids, we achieved the first synthesis of a lysophosphatidylinositol, EhPIa having long fatty acid C30:1, as a partial structure of glycosylphosphatidylinositol (GPI) anchor from the cell membrane of a protozoa, Entamoeba histolytica.

DOI： 10.1039/c6ob01062h

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Tetrahedron Letters  

Lewis acid-catalyzed insertion of isocyanides 2 into nitrogen-sulfur bonds of sulfenamides 1 was developed. This method provided a convenient method for the synthesis of isothioureas 3. Among Lewis acids examined, AlCl3 brought about the best result. Acetic acid assisted one-pot preparation of unsymmetrical ureas was also described.

DOI： 10.1016/j.tetlet.2015.01.096

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry Letters  

The insertion reaction of isocyanides with thiocarbamates and selenocarbamates in the presence of a Pd(0) catalyst to selectively give 2-oxoethanimidothioates and -selenoates is reported. This is the first example of the insertion of an isocyanide into a carbon-heteroatom bond using a transitionmetal catalyst. DFT calculations suggest that the reaction proceeds through a thiopalladation pathway at the migratory insertion process.

DOI： 10.1246/cl.141141

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Heterocycles  

Intramolecular vinylselenation of allenes 1a,b proceeds in the presence of Pd(0) catalyst producing pyridin-2-one derivatives 2a,b having a high degree of unsaturation as a sole product. This cyclization could also be applied to vinylthiolation and to the construction of seven-membered lactams.

DOI： 10.3987/COM-14-S(K)80

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Organic and Biomolecular Chemistry  

The direct sulfenylation and sulfonylation of (sp²)C-H bonds of benzamide derivatives were achieved using a Ni catalyst with the aid of an 8-aminoquinoline moiety as a bidentate directing group. These protocols represent a convenient route for the formation of valuable diaryl sulfides and sulfones in moderate to excellent yields.

DOI： 10.1039/c5ob00149h

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：RSC Advances  

The copper-mediated direct thiolation of carbazole derivatives with disulfides via C(sp²)-H bond cleavage was developed for synthesizing diaryl and alkyl aryl sulfides. This reaction exhibits wide tolerance toward various functional groups giving the products in good yields without any additives or ligands, and can be easily extended to the synthesis of thioethers carrying a benzo[h]quinolone, 2-phenylquinoline, or indole moiety in satisfactory yields.

DOI： 10.1039/c5ra04965b

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Angewandte Chemie - International Edition  

Copper complexes generated in situ from CuCl<inf>2</inf>, alkyl Grignard reagents, and 1,3-dienes play important roles as catalytic active species for the 1,2-hydroalkylation of 1,3-dienes by alkyl fluorides through C-F bond cleavage. The alkyl group is introduced to an internal carbon atom of the 1,3-diene regioselectively, thus giving rise to the branched terminal alkene product. Making the switch: A copper-hydride species, generated by the treatment of a copper salt with alkyl Grignard reagents, catalyzes the 1,2-hydroalkylation of 1,3-dienes by alkyl fluorides and Grignard reagents. The alkyl group of the alkyl fluoride is selectively introduced to an internal carbon atom of the 1,3-diene and the Grignard reagent acts as hydride source to give the branched terminal alkene, even in the presence of alkenes and alkynes.

DOI： 10.1002/anie.201503288

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Organometallics  

The cis insertion of dimethyl acetylenedicarboxylate (DMAD, 2) into the Au-P bond of Au(SAr)(PAr′<inf>3</inf>) (1) occurs selectively at room temperature to give adduct 3, whose X-ray crystallographic analysis exhibits the predominant character of an alkenylphosphorus zwitterion complex. The first-order kinetics with respect to 1 and 2 and the large negative value of ΔS^‡ indicate that the reaction proceeds through the coordination of 2 to 1 followed by a concerted inner-sphere nucleophilic attack of PPh<inf>3</inf> on the coordinated triple bond. In contrast, Au(Cl)(PPh<inf>3</inf>) (4) does not react with 2 even at 60 °C. However, the tricoordinated 16-electron complex Au(Cl)(PPh<inf>3</inf>)<inf>2</inf> (5) quite successfully reacts with 2 to produce insertion product 6, demonstrating that two PPh<inf>3</inf> ligands are required for the reaction. (Chemical Presented).

DOI： 10.1021/acs.organomet.5b00078

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：日本語   出版者・発行元：公益社団法人 石油学会  

最小の共役ジエンである1,3-ブタジエンの遷移金属触媒とアルキル化剤としてフッ化アルキルを用いた反応により長鎖かつ官能基化された不飽和炭化水素が得られることを見出した。銅触媒とアルキルグリニャール試薬を用いると、1,3-ブタジエンの内部炭素にアルキル基が導入された生成物が得られた。一方、ニッケル触媒とアリールグリニャール試薬を用いることによりブタジエンの二量化を伴い、アルキル基とアリール基がそれぞれ1,6-オクタジエン骨格の3および8位に導入された生成物が得られた。

DOI： 10.11523/sekiyu.2015.0_17

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Organic Chemistry  

Palladium catalyzes the intermolecular chalcogenation of carbazole, 2-phenylpyridine, benzo[h]quinolone, and indole derivatives with disulfides and diselenides via selective C-H bond cleavage, providing a convenient route to thio and selenoethers.

DOI： 10.1021/jo502402d

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Organic Chemistry  

Cross-coupling of alkyl halides with alkyl Grignard reagents proceeds with extremely high TONs of up to 1230000 using a Cu/unsaturated hydrocarbon catalytic system. Alkyl fluorides, chlorides, bromides, and tosylates are all suitable electrophiles, and a TOF as high as 31200 h^-1 was attained using an alkyl iodide. Side reactions of this catalytic system, i.e., reduction, dehydrohalogenation (elimination), and the homocoupling of alkyl halides, occur in the absence of additives. It appears that the reaction involves the β-hydrogen elimination of alkylcopper intermediates, giving rise to olefins and Cu-H species, and that this process triggers both side reactions and the degradation of the Cu catalyst. The formed Cu-H promotes the reduction of alkyl halides to give alkanes and Cu-X or the generation of Cu(0), probably by disproportionation, which can oxidatively add to alkyl halides to yield olefins and, in some cases, homocoupling products. Unsaturated hydrocarbon additives such as 1,3-butadiene and phenylpropyne play important roles in achieving highly efficient cross-coupling by suppressing β-hydrogen elimination, which inhibits both the degradation of the Cu catalyst and undesirable side reactions.

DOI： 10.1021/jo501006u

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Heteroatom Chemistry  

Decarbonylative rearrangement of seleno- and tellurocarbamates carrying an allenyl group on the nitrogen was found to proceed in the presence of a palladium catalyst to afford 3-chalcogeno-1-azadienes. This transformation may involve oxidative addition of Pd to a carbon-chalcogen bond, decarbonylation from a carbamoylpalladium unit (R2N-C(O)-PdChPh: Ch = Se or Te), Pd shift, and reductive elimination.

DOI： 10.1002/hc.21217

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Organometallic Chemistry  

The treatment of CpRu(Cl)(PPh3)2 with MeC(O)X offers a very convenient procedure for the synthesis of CpRu(X)(PPh3) 2. The proposed mechanism involves an intermediate produced by the concerted liberation of PPh3 by the incoming MeC(O)X and the subsequent subtraction of the X atom by the Ru atom to form a radical pair. © 2014 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jorganchem.2014.06.018

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of the American Chemical Society  

Anionic diarylrhodium complexes, generated by reacting [RhCl(cod)] 2 with 2 equiv of aryl Grignard reagents, were found to be effective active catalysts in cross-coupling reactions of vinyl ethers with aryl Grignard reagents, giving rise to the production of vinyl arenes. In this catalytic system, vinyl-O bonds were preferably cleaved over Ar-O or Ar-Br bonds. A lithium rhodate complex was isolated, and its crystal structure was determined by X-ray crystallography. © 2014 American Chemical Society.

DOI： 10.1021/ja5043534

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Synthesis (Germany)  

The cross-coupling of alkyl (pseudo)halides with alkyl Grignard reagents is catalyzed efficiently by a cobalt(II) chloride-lithium iodide-1,3-diene catalytic system, which provides a new synthetic tool for constructing sp 3 carbon chains. This system is particularly useful for creating quaternary carbon centers via the use of tertiary alkyl Grignard reagents. Various functional groups including esters, amides and carbamates are well tolerated. © 2014 Nougué et al.; licensee BioMed Central Ltd.

DOI： 10.1055/s-0033-1341152

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of the American Chemical Society  

The cobalt-catalyzed cross-coupling of alkyl (pseudo)halides with alkyl Grignard reagents in the presence of 1,3-butadiene as a ligand precursor and LiI is described. Sterically congested quaternary carbon centers could be constructed by using tertiary alkyl Grignard reagents. This reaction proceeds via an ionic mechanism with inversion of stereochemistry at the reacting site of the alkyl halide and is compatible with various functional groups. The use of both 1,3-butadiene and LiI was essential for achieving high yields and high selectivities. © 2013 American Chemical Society.

DOI： 10.1021/ja404285b

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry - A European Journal  

Synthetic methods: The Ni-catalyzed alkylation of 2-(methylthio) benzothiazoles through C-S bond cleavage is reported. Reactions with various secondary alkyl nucleophiles proceeded efficiently in the presence of 1,3-butadiene as an additive. This reaction was proposed to proceed by σ-bond metathesis between the thioether and a bis(π-allyl)nickel complex or by an addition/elimination mechanism involving the C=34;N double bond of the benzothiazoles (see scheme). Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI： 10.1002/chem.201203413

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry - A European Journal  

The knights who say Ni: A practical and convenient synthetic route to fatty acids involves the Ni-catalyzed alkyl-alkyl cross-coupling of bromoalkanoic acids and alkyl Grignard reagents in the presence of 1,3-butadiene as an additive (see scheme). Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI： 10.1002/chem.201204222

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PubMed

その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry Letters  

Complexes with the formula Au(X)(L) (X = Br and I; L = PPh3 and IPr) were conveniently prepared by a quite simple procedure using the treatment of Au(Cl)(L) with MeC(O)X and the subsequent evaporation under reduced pressure. The mechanistic study by DFT calculation with M06 functional supported that the reaction proceeded through σ-bond metathesis where Cl atom underwent a more roundabout course than Br atom did. © 2013 The Chemical Society of Japan.

DOI： 10.1246/cl.130335

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Organic Letters  

A straightforward and efficient method for the rhodium-catalyzed intermolecular oxidative cross-coupling of arenes and heteroarenes with thio- and selenophene derivatives (chalcogenophenes) via double C-H bond cleavage has been developed by using Cu(OAc)2/AgSbF6 as an oxidant. The reaction is applicable to a wide range of (hetero)arenes carrying a directing group and chalcogenophenes to yield substituted biaryl heterocyclic derivatives and oligothiophene derivatives in moderate to high yields. © 2013 American Chemical Society.

DOI： 10.1021/ol400230y

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PubMed

その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Organometallics  

The novel utility of the ligand exchange reaction between M-X and RC(O)X′ (X, X′ = halogen; R = aryl, alkyl) is described. The relative ΔGs (ΔΔGs) of the oxidative additions of acid halides RC(O)X to M(PPh3)2Ln (M = Pt, Pd) were determined using the halogen-exchange reactions between X of trans-M(X)[C(O)R](PPh3)2 and X′ of RC(O)X′. Experimental thermodynamics data are reasonably consistent with those obtained by density functional theory (DFT) calculations. Activation parameters obtained by experiments as well as a systematic DFT study supported the fact that reactions occurred through slightly distorted quadrangular pentacoordinated σ-bond metatheses, in which the Cl atom underwent a more indirect course than the Br atom. Moreover, exchange reactions were employed as the accessible prototype for the conversion of halogen ligands of nickel triad complexes into heavier halogen ligands. © 2013 American Chemical Society.

DOI： 10.1021/om400157a

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Organic and Biomolecular Chemistry  

The rhodium-catalyzed intramolecular direct arylation of imidazole and benzimidazole derivatives via double C-H bond activation is described. This approach provides new access to a wide range of imidazo and benzimidazo[2,1-a] isoquinoline derivatives in moderate to high yields. This reaction provides an alternative method to the known Pd-catalyzed intramolecular oxidative cross-coupling reactions. © 2013 The Royal Society of Chemistry.

DOI： 10.1039/c3ob27396b

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Physical Chemistry A  

Lithium dialkylcuprates may potentially form mixed aggregates with many species in solution. Those include excess alkyllithium used to prepare the cuprate, lithium halide, and lithium cyanide from cuprate preparation and from coupling reactions with alkyl halides, higher order cuprates, and species resulting from incomplete cuprate reactions. The M06 DFT method was used to elucidate the structures and energies of formation of potential mixed aggregates. A comparison was made to available experimental data. © 2012 American Chemical Society.

DOI： 10.1021/jp3034424

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemical Communications  

Cu-catalyzed cross-coupling of unactivated secondary alkyl iodides with alkyl Grignard reagents in the presence of 1,3-butadiene as a ligand precursor was developed. The use of 1,3-butadiene resulted in improved yields of alkyl–alkyl products with improved selectivities. 2012 © The Royal Society of Chemistry.

DOI： 10.1039/c2cc34847k

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Tetrahedron  

Pd(0)-catalyzed vinylselenation of allenes was found to proceed efficiently in the presence of P(p-MeC 6H 4) 3 as a ligand to afford the corresponding 2-selenomethyl-1,3-dienes. This reaction is highly regioselective and vinyl selenides added to the terminal double bond of the allenes exclusively to introduce the vinyl group at the inner carbon and the selenium moiety at the terminal carbon. The stereochemistry of the double bond of the vinyl selenides was perfectly retained. © 2012 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2012.10.003

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：日本語   出版者・発行元：公益社団法人 石油学会  

銅触媒とブタジエン存在下、二級ヨウ化アルキルとグリニャール試薬とのクロスカップリング反応が効率よく進行することを見いだした。一方、先にグリニャール試薬で処理した銅触媒存在下グリニャール試薬とフッ化アルキルで処理することでブタジエンの1,2-ヒドロアルキル化が進行することを見いだしたので合わせて報告する。いずれの反応もC-C結合の形成を伴い三級炭素中心が生成することから、分岐炭素骨格を構築する上で有用な手法である。

DOI： 10.11523/sekiyu.2012f.0_135

記述言語：日本語   出版者・発行元：公益社団法人 石油学会  

クロスカップリング反応は炭素骨格を構築する上で最も有効な手段の一つであり、様々な触媒系が開発されている。しかし、アルキルハライドとアルキル有機金属試薬とのクロスカップリング反応にはまだ解決すべき多くの問題点がある。その一つが、触媒効率があまり高くなく、これまでに報告されている最高のものでも、TONが数千ほどしかないことである。本研究では触媒効率の向上を目指し、銅触媒を用いてアルキルハライドとアルキルGrignard試薬とのカップリング反応を検討した結果、最高TON400,000を達成したので報告する。

DOI： 10.11523/sekiyu.2012f.0_134

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ACS Catalysis  

A catalytic amount of 4-dimethylaminopyridine showed drastic additive effects on transesterification catalyzed by the μ4-oxo- tetranuclear zinc cluster Zn4(OCOCF3)6O, enhancing the catalytic activity by more than 15-fold. The new catalyst system facilitates transesterification of less reactive sterically demanding esters and alcohols. © 2011 American Chemical Society.

DOI： 10.1021/cs200224b

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry Letters  

Kinetic studies of the nickel-catalyzed cross-coupling reaction of alkyl bromides, iodides, and tosylates with butyl Grignard reagents in the presence of butadiene were performed. The reaction rate was first order with respect to the halides and the nickel catalyst. The butyl Grignard reagent, at concentrations of ca. 0.4M or higher, had little effect on the reaction rate. The relative reactivities and activation parameters were determined for these alkyl halides and a tosylate. © 2011 The Chemical Society of Japan.

DOI： 10.1246/cl.2011.1024

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Tetrahedron Letters  

Nickel and palladium-containing perovskites, LaFe0.8Ni 0.2O3 (LFNO) and LaFe0.95Pd 0.05O3 (LFPO), could be employed as effective catalyst sources for the cross-coupling of nonactivated alkyl halides and tosylates with Grignard reagents in the presence of conjugated dienes. The reaction proceeded efficiently at room temperature or below using only ca. 1 mol % of catalysts with respect to Ni or Pd and the perovskites were reused without considerable loss of activity. © 2010 American Chemical Society.

DOI： 10.1016/j.tetlet.2010.12.011

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Angewandte Chemie - International Edition  

Thinking outside the box: A newly developed C1-symmetric Rh/Phebox complex efficiently catalyzed the asymmetric alkynylation of α-ketoester 1 with various aryl and alkyl substituted terminal alkynes to provide the corresponding chiral tertiary propargylic alcohols with up to 99 % ee (see scheme; TMS=trimethylsilyl). Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI： 10.1002/anie.201100252

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   出版者・発行元：Chemical Society Reviews  

Cross-coupling reactions have become indispensable tools for creating carbon–carbon (or heteroatom) bonds in organic synthesis. Like in other important transition metal catalyzed reactions, such as metathesis, addition, and polymerization, unsaturated compounds are usually employed as substrates for cross-coupling reactions. However during the past decade, a great deal of effort has been devoted to the use of alkyl halides as saturated compounds in cross-coupling reactions, which has resulted in significant progress in this undeveloped area by introducing new effective ligands. Many useful catalytic systems are now available for synthetic transformations based on Csp3–Csp3, Csp3–Csp2 and Csp3–Csp bond formation as complementary methods to conventional Csp2–Csp2, Csp2–Csp and Csp–Csp coupling. This tutorial review summarizes recent advances in cross-coupling reactions of alkyl halides and pseudohalides catalyzed by a palladium complex. © 2011 The Royal Society of Chemistry.

DOI： 10.1039/c1cs15129k

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Yuki Gosei Kagaku Kyokaishi/Journal of Synthetic Organic Chemistry  

Transition metal catalyzed alkylation reactions resulting in cross-coupling and multicomponentcoupling are described. These reactions proceed efficiently under mild conditions using a combination of transition metal catalysts and alkyl (pseudo)halides in the presence of Grignard reagents and represent the practical routes to the alkylation of sp3-, sp2-, and sp-carbons. Anionic transition metal complexes play important roles as active catalytic species for SN2 and electron transfer processes in reactions with alkyl halides. The carbometalation of C-C unsaturated bonds with alkylmetal species is also a promising tool for the introduction of alkyl groups.

DOI： 10.5059/yukigoseikyokaishi.69.1271

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Tetrahedron Letters  

The allylaryloxylation of an internal alkyne by allyl aryl ethers was realized by Pd(dba)2/P(OPh)3 catalyst system to afford cis adducts in moderate yields. © 2011 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2011.08.065

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Organic Letters  

A silver-catalyzed carbomagnesiation of alkynes with alkyl halides and Grignard reagents afforded alkenyl Grignard reagents regioselectively, where the alkyl group of the alkyl halide, but not that of the Grignard reagent, was introduced into the alkyne. Application to δ-haloalkylacetylenes yielded cyclopentanes or a tetrahydrofuran containing an exo-methylene substituent via 5-exo-dig cyclization. © 2011 American Chemical Society.

DOI： 10.1021/ol2018664

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   出版者・発行元：AMER CHEMICAL SOC  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry - A European Journal  

A new catalytic deacylation of acetates and benzoates through transesterification with methanol was developed (see scheme). Reactions with various acidand nucleophile-sensitive functional groups proceeded efficiently in the presence of a catalytic amount of the tetranuclear zinc cluster. The present catalysis is applicable to less-reactive tertiary acetates, the deacylation of which is difficult to achieve by transesterification with other catalysts. © 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI： 10.1002/chem.201000960

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：日本語   出版者・発行元：公益社団法人 石油学会  

ロジウム錯体存在下、フェニルビニルエーテルとアリールグリニャール試薬を反応させたところ、エーテルの炭素－酸素結合の切断を伴うアリール化反応が起こり、スチレン誘導体が得られた。本反応条件下ではビニル炭素－酸素結合が選択的に反応し、フェニル炭素－酸素結合の切断は起こらない。基質としてビニルエーテルの代わりにビニルエステル、もしくはシリルエノールエーテルを用いることも可能である。

DOI： 10.11523/sekiyu.2010f.0.6.0

記述言語：日本語   出版者・発行元：公益社団法人 石油学会  

当研究室では、分子内に末端アレンを持つカルバモカルコゲナートを0価Pd触媒で処理すると、アレンへの選択的付加により対応するα,β-不飽和ラクタムが得られることを報告している。そこで今回私は、窒素に直接アレニル基のついた基質で同様の反応を行ったところ、ラクタムの代わりに脱COを伴った転位生成物が得られた。またこれはN-CO-PdからのCOの脱離やアザ－πアリルパラジウム種の生成など珍しい経路を含んでいると考えられる。

DOI： 10.11523/sekiyu.2010f.0.22.0

記述言語：日本語   出版者・発行元：Yuki Gosei Kagaku Kyokaishi/Journal of Synthetic Organic Chemistry  

Over the last few decades, the quest for environmentally benign chemical transformations has become an important topic in both industrial and academic research. We developed several highly atom-economical direct reactions, such as direct conversion of esters to oxazolines and transeste-rification, catalyzed by μ4-oxo-tetranuclear zinc cluster Zn4(OCOCF 3)6O (1b). Because the reaction conditions are almost neutral, various acid-sensitive functionalities (THP ether, TES ether, Boc carbamate, and so on) persisted and no epimerization of α-position of ester occurred. The most attractive highlight of the zinc cluster catalysis is that hydroxyl groups are selectively acylated in the presence of primary and secondary aliphatic amino groups. Such advantageous catalytic performance is due to assembled metal ions that serve as a functional model of metalloenzyme containing more than two metal ions, but different from mononuclear catalysts and other previously reported catalysts.

DOI： 10.5059/yukigoseikyokaishi.67.494

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Synlett  

In the presence of a Zn-cluster catalyst, alcohols are efficiently converted to the corresponding acetate just by refluxing in EtOAc. The mild reaction conditions enabled the reactions of various functionalized alcohols to proceed in good to excellent yield. Moreover, even when a large excess of the acetyl donor is used, the hydroxyl groups are selectively acetylated in the presence of highly nucleophilic aliphatic amino groups, approaching chemoselectivity to that of enzymatic system. © Georg Thieme Verlag Stuttgart.

DOI： 10.1055/s-0029-1217335

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemical Communications  

Density functional theory calculations demonstrate that Al(iii)-catalyzed conversion of glyoxal to glycolic acid proceeds via a 7-membered dual Lewis acid-hydrogen bonding activation transition state of the 1,2-hydride shift, rather than the previously proposed 5-membered metal-alkoxide chelate activation transition state. © The Royal Society of Chemistry 2009.

DOI： 10.1039/b902729g

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of the American Chemical Society  

Acylation of alcohols and amines is one of the most fundamental reactions. Due to the greater nucleophilicity of the amino group compared to the hydroxyl group, complete N-acylation occurs. Only an enzymatic reaction can promote a highly selective O-acylation reaction, and there are no examples using an artificial catalyst. Here we report that the tetranuclear zinc cluster Zn4(OCOCF3)6O efficiently catalyzes highly chemoselective O-acylation in the presence of primary and secondary alkyl amines. Our results suggest the high potential of the zinc cluster as the core structure of an artificial enzyme to realize further enzyme-like chemoselective reactions. Copyright © 2008 American Chemical Society.

DOI： 10.1021/ja711349r

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Organic Chemistry  

(Chemical Equation Presented) A new catalytic transesterification promoted by a tetranuclear zinc cluster was developed. The mild reaction conditions enabled the reactions of various functionalized substrates to proceed in good to high yield. A large-scale reaction under solvent-free conditions proceeded with a low E-factor value (0.66), indicating the high environmental and economical advantage of the present catalysis. © 2008 American Chemical Society.

DOI： 10.1021/jo800625v

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   出版者・発行元：Journal of Organic Chemistry  

(Chemical Equation Presented) 5-Endo-dig cycloisomerization of 1,4- and 1,2,4- mostly aryl-substituted but-3-yn-1-ones in the presence of a catalytic amount of zinc chloride etherate (10 mol %) in dichloromethane at room temperature gave 2,5-di- and 2,3,5-trisubstituted furans in high yields (85-97%). DSC studies confirmed that a solely thermal process does not take place. A relevant catalytic process, employing μ-oxo-tetranuclear zinc cluster Zn4(OCOCF3)6O, yielded bicyclic furopyrimidine nucleosides, when starting from acetyl-protected 5-alkynyl-2′-deoxyuridines (85-86%). Furopyrimidine was deprotected or simultaneously converted into pyrrolopyrimidine nucleoside. The time/concentration dependence for the reaction of 1-phenyl-4-(4-methylphenyl) butynone to 2-(4-methylphenyl)-5-phenylfuran displayed first-order kinetics with the rate dependent on catalyst concentration. The plot of In K0bS versus In[ZnCl2 indicated first-order cycloi-somerization, as referred to ZnCl2 concentration, using both NMR and UV-vis reaction monitoring. The crystal structure of propyl furopyrimidine nucleoside (orthorhombic, P212121, a/b/c = 5.684(2)/6.682(2)/36.02(2) Å, Z = 4) shows C2′-endo deoxyribose puckering, and the base is found in the anti position in crystalline form. © 2008 American Chemical Society.

DOI： 10.1021/jo8007995

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その他リンク： http://orcid.org/0000-0002-6663-3826

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemical Communications  

The tetranuclear zinc cluster Zn4(OCOCF3) 6O catalyzes the direct conversion of esters, lactones, and carboxylic acids to oxazolines with remarkable chemoselectivity. © The Royal Society of Chemistry 2006.

DOI： 10.1039/b605066b

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その他リンク： http://orcid.org/0000-0002-6663-3826