2016 Fiscal Year Final Research Report
Development of Enantioselective Synthesis of Allenes Using Chirality Transfer from a Chiral Carbanion
Project/Area Number |
15K14929
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Research Category |
Grant-in-Aid for Challenging Exploratory Research
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Allocation Type | Multi-year Fund |
Research Field |
Chemical pharmacy
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Research Institution | Hiroshima University |
Principal Investigator |
Takeda Kei 広島大学, 医歯薬保健学研究院(薬), 教授 (30135032)
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Project Period (FY) |
2015-04-01 – 2017-03-31
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Keywords | 不斉反応 / アレン / シアニドイオン / キラルカルバニオン / 相間移動触媒 |
Outline of Final Research Achievements |
Reactions of γ-bromo-α,β,γ,δ-unsaturated acylsilanes with KCN and quaternary ammonium bromide derived from cinchona alkaloids afforded nonracemic 2-cyano-2-siloxyvinylallenes via a tandem process that involves a nucleophilic attack of a cyanide ion and a Brook rearrangement-induced conjugate vinylic 1,4-elimination. Based on this result and on the stereochemical outcome of the reaction using hydride ion as a chiral source, we propose a reaction pathway in which a Brook rearrangement-mediated vinylic conjugate 1,4-elimination occurs in a syn alignment between the C-Br bond and C-Si bond in the silicate intermediate. The finding that reactions using a chiral cyanide ion source provided nonracemic allene derivatives opens a new perspective in the enantioselective synthesis of highly functionalized allene derivatives.
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Free Research Field |
有機合成化学
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