| Yoichiro Kuninobu | Last modified date：2024.04.19 |
Professor /
Department of Fundamental Organic Chemistry
Institute for Materials Chemistry and Engineering
Institute for Materials Chemistry and Engineering
Graduate School
Undergraduate School
工学部 融合基礎工学科
Other Organization
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Homepage
https://kyushu-u.elsevierpure.com/en/persons/yoichiro-kuninobu
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Homepage of Kuninobu Lab, Institute for Materials Chemistry and Engineering (Department of Molecular and Material Sciences, Interdisciplinary Graduate School of Engineering Sciences) .
Phone
092-583-8855
Fax
092-583-8855
Academic Degree
Doctor of Science
Country of degree conferring institution (Overseas)
No
Field of Specialization
Synthetic Organic Chemistry, Organometallic Chemistry, Structural Organic Chemistry, Organic Materials Chemistry
ORCID(Open Researcher and Contributor ID)
0000-0002-8679-9487
Total Priod of education and research career in the foreign country
00years00months
Outline Activities
In our laboratory, we are trying to solve energy and environmental problems through creation of high performance catalysts, development of practical organic synthesis reactions, and creation of high-performance organic functional materials.
Research
Research Interests
Membership in Academic Society
- We create novel transition metal catalysts which can realize high activity and selectivity, and develop highly efficient and practical synthetic organic reactions, such as C-H transformations. We also create high-performance organic functional materials, such as pi-conjugated molecules and polymers. We aim to solve energy and environmental problems through these projects.
keyword : Catalytic Reaction, Catalyst Design, C-H Bond Transformation, pi-Conjugated System, Polymer
2017.02.
Papers
| 1. | Mori, T.; Yoshigoe, Y.; Kuninobu, Y., Control of Multicolor and White Emissions by Tuning Equilibrium Between Fluorophores, Lewis Acids, and Their Complexes Using Polymers, Angew. Chem. Int. Ed. , 10.1002/anie.201903408, 58, 41, 14457-14461, 2019.10, [URL]. |
| 2. | Xu Lu, Yusuke Yoshigoe, Haruka Ida, Mitsumi Nishi, Motomu Kanai, Yoichiro Kuninobu, Hydrogen Bond-Accelerated meta-Selective C-H Borylation of Aromatic Compounds and Expression of Functional Group and Substrate Specificities, ACS Catalysis, 10.1021/acscatal.8b05005, 9, 3, 1705-1709, 2019.03, We found that meta-selective C-H borylation of aromatic compounds was accelerated when using urea moiety-containing bipyridine-type ligands unlike in cases involving a bipyridine-type ligand without the urea moiety. The acceleration was due to the recognition and capture of the aromatic substrates by the urea moiety of the ligand by hydrogen bonding. The acceleration was further enhanced by modifying the electronic and steric properties of the ligand. The functional group and substrate specificities were also observed using the urea moiety-containing ligands.. |
| 3. | Takayuki Wakaki, Takaya Togo, Daisuke Yoshidome, Yoichiro Kuninobu, Motomu Kanai, Palladium-catalyzed synthesis of diaryl ketones from aldehydes and (hetero)aryl halides via C-H bond activation, ACS Catalysis, 10.1021/acscatal.8b00440, 8, 4, 3123-3128, 2018.04, We developed a palladium-catalyzed C-H transformation that enabled the synthesis of ketones from aldehydes and (hetero)aryl halides. The use of picolinamide ligands was key to achieving the transformation. Heteroaryl ketones, as well as diaryl ketones, were synthesized in good to excellent yields, even in gram-scale, using this reaction. Results of density functional theory (DFT) calculations support the C-H bond activation pathway.. |
| 4. | Li, H.-L.; Kuninobu, Y.; Kanai, M., Lewis Acid-Base Interaction-Controlled ortho-Selective C-H Borylation of Aryl Sulfides, Angew. Chem. Int. Ed. , 10.1002/anie.201610041, 56, 6, 1495-1499, 2017.02. |
| 5. | Masahiro Nagase, Yoichiro Kuninobu, Motomu Kanai, 4-Position-Selective C-H Perfluoroalkylation and Perfluoroarylation of Six-Membered Heteroaromatic Compounds, Journal of the American Chemical Society, 10.1021/jacs.6b01753, 138, 19, 6103-6106, 2016.05, The first 4-position-selective C-H perfluoroalkylation and perfluoroarylation of six-membered heteroaromatic compounds were achieved using nucleophilic perfluoroalkylation and perfluoroarylation reagents. The regioselectivity was controlled by electrophilically activating the heteroaromatic rings, while sterically hindering the 2-position, with a sterically bulky borane Lewis acid. The reaction proceeded in good yield, even in gram scale, and by a sequential reaction without isolating the intermediates. This reaction could be applied to late-stage trifluoromethylation of a bioactive compound.. |
| 6. | Yoichiro Kuninobu, Kanae Yamauchi, Naoya Tamura, Takayuki Seiki, Kazuhiko Takai, Erratum Rhodium-catalyzed asymmetric synthesis of spirosilabifluorene derivatives (Angewandte Chemie - International Edition (2013) (52) DOI: 10.1002/anie.201207723), Angewandte Chemie - International Edition, 10.1002/anie.201511117, 55, 6, 1948, 2016.02. |
| 7. | Yoichiro Kuninobu, Haruka Ida, Mitsumi Nishi, Motomu Kanai, A meta-selective C-H borylation directed by a secondary interaction between ligand and substrate, Nature Chemistry, 10.1038/nchem.2322, 7, 9, 712-717, 2015.09, Regioselective C-H bond transformations are potentially the most efficient method for the synthesis of organic molecules. However, the presence of many C-H bonds in organic molecules and the high activation barrier for these reactions make these transformations difficult. Directing groups in the reaction substrate are often used to control regioselectivity, which has been especially successful for the ortho-selective functionalization of aromatic substrates. Here, we describe an iridium-catalysed meta-selective C-H borylation of aromatic compounds using a newly designed catalytic system. The bipyridine-derived ligand that binds iridium contains a pendant urea moiety. A secondary interaction between this urea and a hydrogen-bond acceptor in the substrate places the iridium in close proximity to the meta-C-H bond and thus controls the regioselectivity. 1 H NMR studies and control experiments support the participation of hydrogen bonds in inducing regioselectivity. Reversible direction of the catalyst through hydrogen bonds is a versatile concept for regioselective C-H transformations.. |
| 8. | Yoichiro Kuninobu, Masahiro Nagase, Motomu Kanai, Benzylic C(sp3)-H Perfluoroalkylation of Six-Membered Heteroaromatic Compounds, Angewandte Chemie - International Edition, 10.1002/anie.201505335, 54, 35, 10263-10266, 2015.08, Successful benzylic C(sp3)-H trifluoromethylation, pentafluoroethylation, and heptafluoropropylation of six-membered heteroaromatic compounds were achieved as the first examples of a practical benzylic C(sp3)-H perfluoroalkylation. In these reactions, BF2CnF2n+1 (n=1-3) functioned as both a Lewis acid to activate the benzylic position and a CnF2n+1 (n=1-3) source. The perfluoroalkylation proceeded at both terminal and internal positions of the alkyl chains. Perfluoroalkylated products were obtained in moderate to excellent yields, even on gram scale, and in a sequential procedure without isolation of the intermediates. By using this method, trifluoromethylation of a bioactive compound, as well as introduction of a CF3 group into a bioactive molecular skeleton, proceeded regioselectively.. |
| 9. | Zhen Wang, Yoichiro Kuninobu, Motomu Kanai, Palladium-catalyzed oxirane-opening reaction with arenes via C-H bond activation, Journal of the American Chemical Society, 10.1021/jacs.5b02435, 137, 19, 6140-6143, 2015.05, We achieved a palladium-catalyzed C-H activation/C-C coupling reaction between arenes with a pyridyl, aminoquinolinyl, imino, or amide directing group, and oxiranes. The reaction proceeded at room temperature without any additives and tolerated a wide variety of functional groups, and the products were obtained in good to excellent yields, even on gram scale. This is the first example of a transition-metal-catalyzed intermolecular direct coupling reaction between a C-H bond of aromatic compounds and a carbon atom of oxiranes via C-H bond activation. By using N-methoxybenzamide as a substrate, we obtained 3-substituted isochroman-1-ones in one pot. The coupling reaction proceeded with stereoretention. Kinetic isotope effect experiments suggested that C-H bond activation is the rate-determining step.. |
| 10. | Zhen Wang, Jizhi Ni, Yoichiro Kuninobu, Motomu Kanai, Copper-catalyzed intramolecular C(sp3)-H and C(sp2)-H amidation by oxidative cyclization, Angewandte Chemie - International Edition, 10.1002/anie.201311105, 53, 13, 3496-3499, 2014.03, The first copper-catalyzed intramolecular C(sp3)-H and C(sp 2)-H oxidative amidation has been developed. Using a Cu(OAc) 2 catalyst and an Ag2CO3 oxidant in dichloroethane solvent, C(sp3)-H amidation proceeded at a terminal methyl group, as well as at the internal benzylic position of an alkyl chain. This reaction has a broad substrate scope, and various β-lactams were obtained in excellent yield, even on gram scale. Use of CuCl2 and Ag2CO3 under an O2 atmosphere in dimethyl sulfoxide, however, leads to 2-indolinone selectively by C(sp2)-H amidation. Kinetic isotope effect (KIE) studies indicated that C-H bond activation is the rate-determining step. The 5-methoxyquinolyl directing group could be removed by oxidation. Silver ox: By using a Cu(OAc)2 catalyst and an Ag2CO3 oxidant in dichloroethane solvent, C(sp3)-H amidation proceeded at a terminal methyl group as well as at the internal benzylic position of an alkyl chain. This reaction has a broad substrate scope, and various β-lactams were obtained in excellent yield, even on a gram scale. Use of CuCl2 and Ag2CO3 under an O2 atmosphere led to 2-indolinone selectively synthesized by C(sp2)-H amidation. DMSO=dimethylsulfoxide.. |
| 11. | Qing Xiao, Xiangtai Meng, Motomu Kanai, Yoichiro Kuninobu, Palladium-catalyzed Ci-H fluorosilylation of 2-phenylpyridines Synthesis of silafluorene equivalents, Angewandte Chemie - International Edition, 10.1002/anie.201310293, 53, 12, 3168-3172, 2014.03, Treatment of 2-phenylpyridines with amino(1,3,2-dioxaborolan-2-yl) diphenylsilane produced fluorosilylated 2-phenylpyridines in good to excellent yields under palladium catalysis. This reaction is the first example of Ci-H fluorosilylation. Single-crystal X-ray structure analysis revealed a Lewis acid-base interaction between the silicon and nitrogen atoms, and the obtained fluorosilylated products are silafluorene equivalents. The fluorosilylated products showed stronger fluorescence than the corresponding silafluorene derivative. Treatment of 2-phenylpyridines with amino(1,3,2-dioxaborolan-2-yl) diphenylsilane produced fluorosilylated 2-phenylpyridines in good to excellent yields under palladium catalysis. This reaction is the first example of Ci-H fluorosilylation. A Lewis acid-base interaction exists between the silicon and nitrogen atoms, and the obtained fluorosilylated products can be regarded as silafluorene equivalents.. |
| 12. | Tomoaki Nishida, Haruka Ida, Yoichiro Kuninobu, Motomu Kanai, Regioselective trifluoromethylation of N-heteroaromatic compounds using trifluoromethyldifluoroborane activator, Nature communications, 10.1038/ncomms4387, 5, 2014.03, Many important drugs, agrochemicals and their lead compounds contain trifluoromethyl group(s). Most processes currently used to access trifluoromethyl group-containing molecules are performed by substitution of the carboxy or trichloromethyl groups using hazardous fluorinating reagents under harsh reaction conditions. Cross-coupling reactions between organohalides or boronic acids/esters and trifluoromethylating reagents are also used. Direct C-H trifluoromethylation of organic molecules, however, is the ideal method of introducing trifluoromethyl group(s). Despite the recent advances in C-H trifluoromethylation of N-heteroaromatic compounds, regioselective C-H trifluoromethylation of six-membered heteroaromatic compounds has yet to be achieved. Herein we present a general and reliable method for the synthesis of trifluoromethyl group-containing N-heteroaromatics through highly regioselective addition of a trifluoromethyl nucleophile to pyridine, quinoline, isoquinoline and two or three heteroatom-containing N-heteroaromatic N-oxides activated by trifluoromethyldifluoroborane. The C-H trifluoromethylation proceeds under mild conditions in gram scale with high functional group tolerance. This method will be useful in both laboratory and industrial processes.. |
| 13. | Shunsuke Sueki, Yuanfang Guo, Motomu Kanai, Yoichiro Kuninobu, Rhenium-catalyzed synthesis of 3-imino-1-isoindolinones by C-H bond activation Application to the synthesis of polyimide derivatives, Angewandte Chemie - International Edition, 10.1002/anie.201306360, 52, 45, 11879-11883, 2013.11, Polyimide solution: Synthesis of the title compounds from aromatic imidates and isocyanates in good to excellent yields by a rhenium-catalyzed C-H bond transformation is described. The reaction also proceeded in high yield on gram scale and could be applied to the synthesis of polyimide derivatives (see figure), which are highly soluble in organic solvents.. |
| 14. | Yoichiro Kuninobu, Takashi Iwanaga, Tetsuya Omura, Kazuhiko Takai, Palladium-catalyzed ortho-selective C-H borylation of 2-phenylpyridine and its derivatives at room temperature, Angewandte Chemie - International Edition, 10.1002/anie.201210328, 52, 16, 4431-4434, 2013.04, Boron delivery: C-H borylation at the ortho-position of aromatic compounds is promoted by the treatment of 2-phenylpyridine, or its derivatives, with 9-borabicyclo[3.3.1]nonane in the presence of a palladium catalyst. This reaction proceeds at room temperature and can be conducted without the palladium catalyst at higher temperatures. In both cases, the regioselectivity is controlled by Lewis acid-base interaction between the boron and nitrogen atoms.. |
| 15. | Yoichiro Kuninobu, Kanae Yamauchi, Naoya Tamura, Takayuki Seiki, Kazuhiko Takai, Rhodium-catalyzed asymmetric synthesis of spirosilabifluorene derivatives, Angewandte Chemie - International Edition, 10.1002/anie.201207723, 52, 5, 1520-1522, 2013.01, Si goes chiral: Treatment of a bis(biphenyl)silane with a catalytic amount of a rhodium complex gave a spirosilabifluorene bearing a quaternary silicon atom. By using a rhodium catalyst with a chiral phosphine ligand (see scheme), asymmetric dehydrogenative cyclization proceeded to give chiral derivatives in good yields and enantioselectivities.. |
| 16. | Yoichiro Kuninobu, Tadamasa Uesugi, Atsushi Kawata, Kazuhiko Takai, Manganese-catalyzed cleavage of a carbon-carbon single bond between carbonyl carbon and α-carbon atoms of ketones, Angewandte Chemie - International Edition, 10.1002/anie.201104704, 50, 44, 10406-10408, 2011.10, Singled out: Treatment of ketones with carbodiimides in the presence of a catalytic amount of either [{HMn(CO)4}3] or [Mn 2(CO)10] gave amides in good to excellent yields. In this reaction, the carbon-carbon single bond of a ketone is cleaved efficiently. The reaction also proceeded by using isocyanates instead of carbodiimides.. |
| 17. | Tomonari Ureshino, Takuya Yoshida, Yoichiro Kuninobu, Kazuhiko Takai, Rhodium-catalyzed synthesis of silafluorene derivatives via cleavage of silicon-hydrogen and carbon-hydrogen bonds, Journal of the American Chemical Society, 10.1021/ja107698p, 132, 41, 14324-14326, 2010.10, The rhodium-catalyzed synthesis of silafluorenes from biphenylhydrosilanes is described. This highly efficient reaction proceeds via both Si-H and C-H bond activation, producing only H2 as a side product. Using this method, a ladder-type bis-silicon-bridged p-terphenyl could also be synthesized.. |
| 18. | Yoichiro Kuninobu, Takashi Matsuki, Kazuhiko Takai, Rhenium-catalyzed regioselective alkylation of phenols, Journal of the American Chemical Society, 10.1021/ja904360k, 131, 29, 9914-9915, 2009.07, (Chemical Equation Presented) Treatment of phenol derivatives with terminal alkenes in the presence of a catalytic amount of a rhenium complex, Re 2(CO)10, gave monoalkylated phenol derivatives in good to excellent yields. This reaction proceeds at the ortho- or para-position of phenols regioselectively.. |
| 19. | Salprima Yudha S, Yoichiro Kuninobu, Kazuhiko Takai, Rhenium-catalyzed synthesis of stereodefined cyclopentenes from β-ketoesters and aliphatic allenes, Angewandte Chemie - International Edition, 10.1002/anie.200803350, 47, 48, 9318-9321, 2008.11, (Chemical Equation Presented) Come on allene: Commercially available [Re2(CO)10] as a catalyst provides five-membered carbocycles in moderate to excellent yields with high stereoselectivity (see scheme). The configuration at each of the three sp3 carbon centers of the ring is defined. The reaction proceeds at the β, γ, and adjacent methylene positions of the allene; previously, similar reactions usually occurred at the α, β, and γ positions of the allene.. |
| 20. | Yoichiro Kuninobu, Yuta Nishina, Takashi Matsuki, Kazuhiko Takai, Synthesis of Cp-Re complexes via olefinic C-H activation and successive formation of cyclopentadienes, Journal of the American Chemical Society, 10.1021/ja805921f, 130, 43, 14062-14063, 2008.10, Treatment of an α,β-unsaturated ketimine with an α,β-unsaturated carbonyl compound in the presence of a rhenium complex, Re2(CO)10, gave a cyclopentadienyl-rhenium complex. This reaction proceeds via rhenium-catalyzed C-H bond activation of an olefinic C-H bond, insertion of an α,β-unsaturated carbonyl compound into a Re-C bond of the alkenylrhenium intermediate, intramolecular nucleophilic cyclization, reductive elimination, elimination of aniline to give a cyclopentadiene derivative, followed by the formation of a cyclopentadienyl-rhenium complex from the cyclopentadiene derivative and the rhenium complex.. |
| 21. | Atsushi Kawata, Kazumi Takata, Yoichiro Kuninobu, Kazuhiko Takai, Indium-catalyzed retro-claisen condensation, Angewandte Chemie - International Edition, 10.1002/anie.200702798, 46, 41, 7793-7795, 2007.10, (Chemical Equation Presented) Retro-aldol reaction: Indium-catalyzed reaction of a 1,3-diketone with an alcohol proceeds under solvent-free conditions by nucleophilic attack of the alcohol on a carbonyl group of the 1,3-diketone and carbon-carbon bond cleavage by a retro-Claisen condensation to give an ester in high yield (see scheme). Using water and an amine as nucleophiles instead of an alcohol gave the corresponding carboxylic acid and amide.. |
| 22. | Yoichiro Kuninobu, Yuta Nishina, Takahiro Takeuchi, Kazuhiko Takai, Manganese-catalyzed insertion of aldehydes into a C-H bond, Angewandte Chemie - International Edition, 10.1002/anie.200702256, 46, 34, 6518-6520, 2007.09, (Chemical Equation Presented) Mn gets in the game: In the presence of a manganese catalyst and a stoichiometric amount of hydrosilane, aldehydes insert into C-H bonds of aromatic rings of compounds with directing groups (see scheme). This first example of a manganese-catalyzed chemical transformation through C-H bond activation gives silyl ethers in good to excellent yields and can also be applied to asymmetric transformation.. |
| 23. | Yoichiro Kuninobu, Eri Ishii, Kazuhiko Takai, Rhenium- and gold-catalyzed coupling of aromatic aldehydes with trimethyl(phenylethynyl)silane Synthesis of diethynylmethanes, Angewandte Chemie - International Edition, 10.1002/anie.200700183, 46, 18, 3296-3299, 2007.06, (Chemical Equation Presented) Very couply! Coupling reactions of propargyl or benzyl alcohols with allyl- or alkynylsilanes proceed efficiently using [{ReBr(CO)3(thf)}2] as catalyst. Additionally, diethynylmethane derivatives were obtained by the reaction of aromatic aldehydes with trimethyl(phenylethynyl)silane in the presence of both the rhenium complex and AuCl (see scheme).. |
| 24. | Yoichiro Kuninobu, Atsushi Kawata, Kazuhiko Takai, Efficient catalytic insertion of acetylenes into a carbon-carbon single bond of nonstrained cyclic compounds under mild conditions, Journal of the American Chemical Society, 10.1021/ja064022i, 128, 35, 11368-11369, 2006.09, A rhenium complex, [ReBr(CO)3(thf)]2, catalyzes the reaction of a 1,3-dicarbonyl cyclic compound with an acetylene to give a medium-sized cyclic compound in excellent yield. By using isocyanide as an additive, the catalytic activity of the rhenium complex changes dramatically, and the insertion of acetylenes into a carbon-carbon single bond occurs under mild conditions. A plausible mechanism is that the reaction proceeds via the formation of a rhenacyclopentene intermediate, ring opening by a retro-aldol reaction, isomerization, and reductive elimination.. |
| 25. | Yoichiro Kuninobu, Yuta Nishina, Chie Nakagawa, Kazuhiko Takai, Rhenium-catalyzed insertion of aldehyde into a C-H bond Synthesis of isobenzofuran derivatives, Journal of the American Chemical Society, 10.1021/ja065643e, 128, 38, 12376-12377, 2006.09, A rhenium complex, [ReBr(CO)3(thf)]2, catalyzed reactions of aromatic ketimines with aldehydes to give isobenzofuran derivatives in good to excellent yields. In contrast to ruthenium and rhodium catalysts, aldehydes, which are polar unsaturated molecules, inserted into the C-H bond after activation by the rhenium complex.. |
| 26. | Yoichiro Kuninobu, Yuta Nishina, Makoto Shouho, Kazuhiko Takai, Rhenium- and aniline-catalyzed one-pot annulation of aromatic ketones and α,β-unsaturated esters initiated by C-H bond activation, Angewandte Chemie - International Edition, 10.1002/anie.200503627, 45, 17, 2766-2768, 2006.04, (Chemical Equation Presented) Several reaction steps, including C-H activation, lead to indene derivatives in good yields in the rhenium-catalyzed reaction of aromatic ketimines and ethyl acrylate. Indene derivatives can also be obtained by the reactions of aromatic ketones with α,β-unsaturated esters in the presence of a catalytic rhenium complex and p-anisidine (see scheme).. |
| 27. | Yoichiro Kuninobu, Yukimi Tokunaga, Atsushi Kawata, Kazuhiko Takai, Insertion of polar and nonpolar unsaturated molecules into carbon-rhenium bonds generated by C-H bond activation Synthesis of phthalimidine and indene derivatives, Journal of the American Chemical Society, 10.1021/ja054216i, 128, 1, 202-209, 2006.01, A rhenium complex, [ReBr(CO)3(thf)]2, catalyzes the reaction of an aromatic aldimine with an isocyanate and an acetylene to give a phthalimidine and an indene derivative in a quantitative yield, respectively. The reactions proceed via C-H bond activation, insertion of the isocyanate or the acetylene, Intramolecular nucleophilic cyclization to the aldimine of the generated amido- or alkenyl-rhenium species, and reductive elimination. In contrast to ruthenium and rhodium catalysts, which are usually employed in this type of reaction, the rhenium catalyst promotes the insertion of a polar unsaturated molecule. This occurs more easily than the insertion of a nonpolar unsaturated molecule.. |
| 28. | Yoichiro Kuninobu, Atsushi Kawata, Kazuhiko Takai, Rhenium-catalyzed formation of indene frameworks via C-H bond activation [3+2] Annulation of aromatic aldimines and acetylenes, Journal of the American Chemical Society, 10.1021/ja0528174, 127, 39, 13498-13499, 2005.10, A rhenium complex, [ReBr(CO)3(thf)]2, catalyzes the reaction of an aromatic aldimine with an acetylene to give an indene derivative in a quantitative yield. The reaction proceeds via C-H bond activation, insertion of the acetylene, intramolecular nucleophilic cyclization, and reductive elimination. In contrast to ruthenium and rhodium catalysts, which are usually employed in this type of reaction, the rhenium catalyst promotes the intramolecular nucleophilic cyclization of the alkenylmetal species generated by insertion of the acetylene.. |
Presentations
- American Chemical Society
- SIS the Society of Iodine Science
- The Society of Fluorine Chemistry, Japan
- The Society of Silicon Chemistry JAPAN
- The Society of Physical Organic Chemistry, Japan
- Kinka Chemical Society, Japan
- The Pharmaceutical Society of Japan
- The Society of Synthetic Organic Chemistry, Japan
- The Chemical Society of Japan
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