Condensation of σt -butyl chloroacetate and ketones by means of magnesium in ether or benzene alone was carried out but the excellent yields of P-hydroxy ester could not be obtained, and the results of the condensation of t -butyl bromoacetate and ketones by means of magnesium and mercuric chloride in benzene were also disappointing. When a mixture of benzene and ether was used as solvent in the condensation of t-butyl chloroacetate and ketone in the presence of magnesium and mercuric chloride, the yields of p-hydroxy esters from cyclohexanone and methyl isobutyl ketone were 62 and 71 % respectively, and were comparable with those of other condensing methods.