A process for the preparation of alpha-n-acyl alpha' chloroketones

摘要

The present invention relates to a process for the preparation of alpha' chloroketones, such as 4-phenyl-3-t-butyloxy-carbonylamino)-2-keto-1-chlorobutane by reacting certain aryl amino acid esters, e.g. N-(2-t-butoxycarbonyl)-L-phenylalanine-4-nitrophenyl ester, with a sulfur ylide compound to form the corresponding keto ylide compound which is then treated with a source of chloride and an organic acid.