| Project/Area Number |
17550096
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Synthetic chemistry
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| Research Institution | Yokohama National University |
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Principal Investigator |
ASAMI Masatoshi Yokohama National University, Faculty of Engineering, Professor, 大学院・工学研究院, 教授 (20134439)
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| Project Period (FY) |
2005 – 2006
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| Project Status |
Completed (Fiscal Year 2006)
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| Budget Amount *help |
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 2006: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 2005: ¥2,600,000 (Direct Cost: ¥2,600,000)
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| Keywords | Catalytic Asymmetric Reaction / Polymer-Bound Reagent / Chiral Secondary Alcohol / Chiral Allyl Alcohol / Zinc Amide / Lithium Dialkylamide / Chiral Pyrrolidine Derivative / Asymmetric Isomerization / キラルジアミン / 金属アミド / (S)-プロリン |
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| Research Abstract |
Convenient method for the preparation of useful chiral compounds was developed by using polymer-bound chiral metal amides prepared from chiral α-amino acids.
Enantioselective addition of diethylzinc to benzaldehyde was examined in the beginning of this project in 2005 using (S)-1-benzyl-2-(anilinomethyl) pyrrolidine or its derivative as chiral catalyst. (R)-1-Phenylpropanol was obtained over 90% ee when (S)-1-benzyl-2-(anilinomethyl)- pyrrolidine or (S)-1-benzyl-2-(p-chloroanilinomethyl) pyrrolidine. Then polymer-bound reagents were prepared by radical copolymerization of styrene, divinylbenzene, and (S)-1-(p-vinylbenzyl)-2-(anilinomethyl) pyrrolidine or (S)-1-(p-vinylbenzyl)-2-(p-chloroanilinomethyl) pyrrolidine. The ee of the resulting (R)-1-phenylpropanol was slightly increased in the reactions using polymer-bound catalysts, namely, zinc amide generated in situ from diethylzinc and the amine..
Catalytic enantioselective isomerization of meso-epoxide to chiral allylic alcohol derivative was examined using polymer-bound chiral lithium amide prepared in situ from butyllithium and polymer-bound chiral diamines derived from (S)-proline or (-)-octahydroindolecarboxylic acid in 2006. Almost the same selectivity as that obtained by the homogeneous reaction using monomeric reagent was achieved using 0.2 equiv of the polymer-bound reagent in the presence of 1.0 equiv of urea derivative in THE at room temperature for 24 h in the reaction with cyclohexene oxide. The reaction was applicable for other meso-epoxides.
In both reactions mentioned above, the selectivity was not changed using the recovered polymer-bound reagent after the reaction.
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