Tris (ethylenedioxybory1) methane (1) with methyllithium yields lithium bis (ethylenedioxybory1) methide (2), which reacts with aldehydes or ketones to give high yields of alkeneboronic esters (3). Oxidation with buffered aqueous hydrogen peroxide'or alkaline sodium perborate results in a simple and efficient conversion of the carbonyl compound to the homologous aldehyde (4). An unexpected and potential-
