High-intensity ultrasound-promoted Reformatsky reactions

Reformatsky reactions of a phenyl ketone, an alpha-bromoester, zinc dust, and a catalytic amount of iodine in dioxane under high-intensity ultrasound (HIU) irradiation from an ultrasonic probe give high yields of beta-hydroxyesters in short reaction times. A series of alkyl phenyl ketones with increasing steric demands of the alkyl group are evaluated as potential electrophiles for the reactions with several alpha-bromoesters, also having increasing steric demands. The Reformatsky reaction under HIU is found to be concentration dependent.