摘要 |
A process for the preparation of an oxirane, aziridine or cyclopropane of formula (I),wherein X is oxygen, NR4 or CHR5; R1 is hydrogen, alkyl, aryl, heteroaromatic, heterocyclic or cycloalkyl; R2 is hydrogen, alkyl, aryl, heteroaromatic, CO2R8, CHR14NHR13, heterocyclic or cycloalkyl; or R1 and R2 join together to form a cycloalkyl ring; R3 and R10 are, independently, hydrogen, alkyl, aryl, heteroaromatic, CO2R8, R83Sn, CONR8R9, trialkylsilyl or triarylsilyl; R4 is an electron withdrawing group; R5 is alkyl, cycloalkyl, aryl, heteroaromatic, SO2R8, SO3R8, COR8, CO2R8, CONR8R9, PO(R8)2, PO(OR8)2 or CN; R8 and R9 are independently alkyl or aryl; and R13 and R14 are independently hydrogen, alkyl or aryl is provided. The process comprises degrading a compound of formula (II), (IIa), (IIb) or (IIc):wherein R3 and R10 are as defined above; Y is a cation; depending on the nature of Y, r is 1 or 2; and L is a suitable leaving group, to form a diazo compound. The diazo compound is reacted with a suitable transition metal catalyst, and the product thereof reacted with a sulphide of formula SR6R7, wherein R6 and R7 are independently alkyl, aryl or heteroaromatic, or R6 and R7 join together to form an optionally substituted ring which optionally includes an additional heteroatom. This product is then reacted with an aldehyde, ketone, imine or alkene.
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