Oxidation of acetals, an orthoester, and ethers by dioxiranes through α-CH insertion

Article abstract of DOI:10.1016/S0040-4039(00)74695-8

Dimethyldioxirane (1a) and methyl(trifluoromethyl)dioxirane (1b) efficiently afford cleavage of acetals and of ketals to carbonyl products under mild, neural conditions. Dialkyl ethers are cleaved to alcohols, aldehydes and/or carboxylic acids, whereas reaction of dioxiranes 1a,b with medium-ring cyclic ethers transforms the latter into lactones, via the corresponding hemiacetals, with no appreciable formation of ring-opened products. The products can be accounted for on grounds of a remarkably selective O-atom insertion by the dioxirane into C-H bonds α to the ether functionality.