2001 Fiscal Year Final Research Report Summary
Stereoselective Synthesis of Medium-sized Carbocyclic Compounds by Tandem Reactions of Cyclic Sulfur Ylides
Project/Area Number |
12650851
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Synthetic chemistry
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Research Institution | SHINSHU UNIVERSITY |
Principal Investigator |
FUJIMOTO Tetsuya SHINSHU UNIVERSITY, FACULTY OF TEXTILE SCIENCE AND TECHNOLOGY, RESEARCH ASSOCIATE, 繊維学部, 助手 (90209099)
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Project Period (FY) |
2000 – 2001
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Keywords | Tandem reactions / Sulfur ylide / Medium-sized carbocycles / Stereoselective / Cyclopropane / Oxirane / Baylis - Hillman adduct |
Research Abstract |
The reaction of a five-membered oxosulfonium ylide with acetates of Baylis - Hillman adducts afforded cycloheptene oxide derivatives with high stereoselectivity in 19-74 % yields via tandem Michael - intramolecular Corey -Chaykovsky reactions. The stereochemistry of resulting compounds was elucidated by an X-ray analysis. From the results of the stereochemistry, an intramolecular Corey reaction was implied to proceed via a rigid bicyclic intermediate containing a chair-form thiacyclohexane ring. In addition, the same reaction of the corresponding sixmembered sulfur ylide was investigated. Consequently, cyclooctene oxide derivatives were obtained in 7-46 % yields as a 4 : 1 mixture of diastereomers relevant to the configuration of sulfur atom. Moreover, the reactions of the cyclic sulfur ylides with aldehydes and enones were attempted in order to evaluate the reactivity of cyclic sulfur ylides. All of the reactions provided the Corey reaction products ( cyclopropane or oxirane derivatives ) in excellent yields. On the other hand, the reaction of the six-membered oxosulfonium ylide with 4-hexen-2-one in the presence of two equimolar amount of base gave a novel eight-membered carbocyclic compound ( 1 : 2 adduct of ylide and enone ) with high stereoselectivity.
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Research Products
(4 results)