An efficient and environmentally benign protocol for the synthesis of vicinal chlorohydroxy and chloromethoxy derivatives in a highly regioselective manner fromolefins using NH4Cl as a chlorine source and oxone as an oxidant in aqueous acetone and methanol is demonstrated. This methodology offers an additive and metal chloride free approach and is endowed with simple reaction conditions, high yields
established that thermal and catalytic decomposition of certain alkyl haloformates affords dialkyl carbonates in addition to alkyl halides. Pyridine(or quinoline)-catalysed decomposition of ethyl and cyclohexyl chloroformate and ethyl fluoroformate affords high yields of alkyl halides, but cyclohexyl fluoroformate yields a significant proportion of dialkyl carbonate. In compounds containing the structural unit
Bromide and chloride anions could be readily oxidized into positive halogens by treating with p-nitrobenzenesulfonyl peroxide. The positive halogens, thus formed, reacted with olefins to give epihalonium ions, which were trapped by oxygen nucleophiles inter- or intramolecularly to afford oxyhalogenated compounds.
Reaction of alkylhypochlorites and xenon difluoride with cyclohexene
作者:Dale F. Shellhamer、Mark J. Horney、Andrew L. Toth、Victor L. Heasley
DOI:10.1016/s0040-4039(00)60891-2
日期:1992.11
Reactions of alkylhypochlorites and xenondifluoride with cyclohexene give primarily 1-chloro-2-fluorocyclohexanes via formation of a complex between xenondifluoride and the alkylhypochlorite.