SYNTHESIS OF EPOXYFERROCENES BY THE OXIDATION OF ACYL-SUBSTITUTED AND ALLYL-SUBSTITUTED FERROCENES WITH DIMETHYLDIOXIRANE

The oxidation of acyl- and allylferrocenes 1 and 2 with dimethyldioxirane as the oxygen transfer agent affords the corresponding epoxides 5 and 6 in fair to good yields. Large excesses of oxidant, high temperatures, and an inert atmosphere (argon) minimize side reactions due to electron transfer processes, through which the ferrocene functionality is oxidized. In general, the allylferrocenes 2 are more reactive than the corresponding acyl derivatives 1. For the phenyl-substituted substrate 2a some C-H insertion (5%) to the acyl derivative 1a is also observed.