| 1. |
Ryoji Hatakenaka, Nanami Nishikawa, Yuji Mikata, Hiroki Aoyama, Kohsuke Yamashita, Yoshihito Shiota, Kazunari Yoshizawa, Yuuya Kawasaki, Katsuhiko Tomooka, Shin Kamijo, Fumito Tani, Efficient Synthesis and Structural Analysis of Chiral 4,4'-Biazulene, Chemistry - A European Journal, doi.org/10.1002/chem.202400098, 2024.03. |
| 2. |
Yuuya Kawasaki, Kazunobu Igawa Tomoya Hayashibara, Yuki Seto,b Yutaro Taniguchi, Katsuhiko Tomooka, Development of DACN-NHS-ester and DACN-maleimide, and their application for the synthesis of artificial hybrid biomolecules, Chem. Commun., 10.1039/d3cc03023g, 2023.09, Yuuya Kawasaki, Kazunobu Igawa,Tomoya Hayashibara, Yuki Seto, Yutaro Taniguchi, Katsuhiko Tomooka. |
| 3. |
Kazunobu Igawa, Kazuhiro Uehara, Yuuya Kawasaki, Katsuhiko Tomooka, Stereochemical study on planar-chiral cyclic molecules using polysaccharide-based column chromatography, Chirality, org/10.1002/chir.23429, 34, 824-832, 2022.09. |
| 4. |
Katsuhiko Tomooka, Chisato Iso, Yukiho Hashimoto, Masaki Suzuki, Yuuya Kawasaki, Kazunobu Igawa, Synthesis, Stereochemical Analysis, and Transformation of Oxa-[7] orthocyclophene, CHEMISTRY LETTERS, 10.1246/cl.220219, 51, 7, 788-790, 2022.07, Planar chiral oxa-[7]orthocyclophene 1a was designed and synthesized with two different synthetic routes. X-ray crystallo-graphic analyses of 1a and its platinum complex revealed a highly distorted ring structure and the absolute stereochemistry of 1a, respectively. Epoxidation and [2,3]-Wittig rearrangement of 1a provided with central chiral molecules, without the loss of enantiomeric purity.. |
| 5. |
Jun-ichi Hayashi, Masaki Suzuki, Maki Shimada, Yuuya Kawasaki, Kazunobu Igawa, Katsuhiko Tomooka, Synthesis and Stereochemical Analysis of Ten-membered Diallylic Nitrogen Cycle and Its Pt-Complex, CHEMISTRY LETTERS, 10.1246/cl.220143, 51, 6, 636-638, 2022.06, Newly synthesized ten-membered diallylic nitrogen cycle, having E- and Z-alkene moieties, shows labile planar-chirality at ambient temperature. VT-NMR experiments revealed the detail of the stereochemical behavior of interconversion of the enantiomers and diastereomers. In sharp contrast, Pt-complex of the nitrogen cycle have more stable planar chirality, and the enantiomers of the Pt-complex were isolated by HPLC using a chiral stationary phase.. |
| 6. |
Igawa, K.; Kawasaki, Y.; Ano, Y.; Kashiwagi, T.; Ogawa, K.; Hayashi, J.; Morita, R. Yoshioka, Y.; Uehara, K.; Tomooka, K., Preparation of Enantioenriched Chiral Organic Molecules by Dynamic Asymmetric Induction from a Outer Chiral Source, CHEMISTRY LETTERS, 10.1246/cl.190170, 48, 7, 726-729, 2019.07. |
| 7. |
Hayashi, J.; Uehara, K.; Ano, Y.; Kawasaki, Y.; Igawa, K.; Tomooka, K., Synthesis and Stereochemical Analysis of Dynamic Planar Chiral Nine-membered Diallylic Amide:Significant Substituent Effect on Stereochemical Stability, Heterocycles, 10.3987/COM-18-S(F)92, 99, 856-864, 2019.06. |
| 8. |
Kawasaki, Y.; Yamanaka, Y.; Seto, Y.; Igawa, K.; Tomooka, K., Synthesis of NMs-DACN: Small and Hydrophilic Click Reaction Device, CHEMISTRY LETTERS, 10.1246/cl.190026, 48, 5, 495-497, 2019.05. |
| 9. |
Kazunobu Igawa, Shin Aoyama, Yuuya Kawasaki, Takeru Kashiwagi, Yuki Seto, Runyan Ni, Naoto Mitsuda, Katsuhiko Tomooka, Thieme Chemistry Journals Awardees: Where Are They Now? One-Pot Synthesis of Versatile Buckle Units for Click Chemistry: 4,8-Diazacyclononynes (DACNs), SYNLETT, 10.1055/s-0036-1588839, 28, 16, 2110-2114, 2017.10, Newly designed buckle units for copper-free click chemistry: 4,8-diazacyclononynes (DACNs) were efficiently synthesized with a one-pot procedure from commercially available 2-butyne-1,4-diol. The synthesized DACNs possess versatile connectors for the introduction of functional units and exhibit high click reactivity.. |
| 10. |
Kazunobu Igawa, Yuuya Kawasaki, Kosuke Nishino, Naoto Mitsuda, Katsuhiko Tomooka, Asymmetric Ozone Oxidation of Silylalkenes Using a C-2-Symmetrical Dialkoxysilyl Group as a Chiral Auxiliary, CHEMISTRY-A EUROPEAN JOURNAL, 10.1002/chem.201402996, 20, 30, 9255-9258, 2014.07, Ozone oxidation of silyl-substituted alkenes, namely silylalkenes, proceeds in an addition-type manner to afford alpha-silylperoxy carbonyl compounds in good to excellent yields, without the formation of normal ozonolysis products. Herein the ozone oxidation of chiral alkenylsilanes prepared from alkynes and a newly designed chiral hydrosilane is reported. The reaction affords silylperoxides with high diastereoselectivity (up to 94% d.r.). The silylperoxides are convertible into enantioenriched chiral acyloins in a stereospecific manner.. |
| 11. |
Yuuya Kawasaki, Youhei Ishikawa, Kazunobu Igawa, Katsuhiko Tomooka, Directing Group-Controlled Hydrosilylation: Regioselective Functionalization of Alkyne, JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 10.1021/ja209553f, 133, 51, 20712-20715, 2011.12, Pt(0)-catalyzed hydrosilylation of unsymmetric alkynes proceeds in a highly regioselective manner with a dimethylvinylsilyl (DMVS) group as the directing group. This hydrosilylation affords a single regioisomer of silylalkenes from propargylic and homopropargylic alcohol derivatives. DMVS also has an accelerating effect that allows group-selective hydrosilylation of the DMVS-attached alkyne prior to that of other alkynes. Combined hydrosilylation and transformation reactions of the resulting silylalkenes afford various tri-substituted alkenes and multi-oxy-functionalized compounds with high regioselectivity from unsymmetric alkynes.. |
| 12. |
Kazunobu Igawa, Yuuya Kawasaki, Katsuhiko Tomooka, Addition-type Oxidation of Silylalkene Using Ozone: An Efficient Approach for Acyloin and Its Derivatives, CHEMISTRY LETTERS, 10.1246/cl.2011.233, 40, 3, 233-235, 2011.03, Acyloins are efficiently synthesized in three steps from alkynes via hydrosilylation followed by an addition-type ozone oxidation and hydrogenation. The key intermediate alpha-silylper-oxy ketone is convertible to not only acyloin but also O-silylated acyloin and diketone.. |
