BETA-IODO KETONES BY PREVOST REACTION OF VINYL CARBINOLS

Treatment of alpha-ethenyl-alpha-phenylbenzenemethanol with iodine and silver acetate in either acetic acid or benzene gave 1,2-diphenyl-3-i odo-1-propanone (6) in 85% yield. Ring enlargements involving similar rearrangements were observed with a number of cyclic vinyl carbinols. In some cases, mixtures of normal Prevost products and rearranged beta -iodo ketones were obtained. The exact scope of this apparently novel reaction remains to be elucidated. Treatment of the beta-iodo ketones with DBU gave the corresponding alpha,beta-unsaturated ketones from wh ich a number of amino ketones and amino alcohols were prepared by conj ugate addition followed by reduction.