Halogenation of #beta#-ALkoxyvinyl Polyhaloalky Ketones: A Convenient Route for the Synthesis of #alpha#-Chloro- or #alpha#-Bromo-#beta#-alkoxyvinyl Polyhaloalkyl Ketones

摘要

A number of #alpha#-chloro- and #alpha#-bromo-#beta#-alkoxyvinyl polyhaloalkyl ketones 4 and 5 were synthesized in high yields by halogenation of #beta#-alkoxyvinyl polyhaloalkyl ketones 1 with chlorine or bromine and further dehydrohalogenation of dihalo-intermediates 2 and 3 with pyridine.The Z configuratioin of ketones 4 and 5 was deduced from X-ray analysis and NMR spectra.Some typical nucleophilic reactions of the title compounds 4 and 5 with amines were carried out to check their reactivity