New reaction mode of the Horner–Wadsworth–Emmons reaction using Sn(OSO₂CF₃)₂ and N-ethylpiperidine

Abstract

Excellent Z or E selectivity is observed in the Horner–Wadsworth–Emmons reactions of methyl bis(trifluoroethyl)phosphonoacetate 2 with aryl alkyl ketones 3a–d or aldehydes 3f,g using Sn(OSO₂CF₃)₂ in the presence of N-ethylpiperidine, which should have a different reaction mode to those using sodium hydride.

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