BENZYLATION VIA TANDEM GRIGNARD REACTION IODOTRIMETHYLSILANE (TMSI) MEDIATED REDUCTION

A method has been developed which allows for the large scale preparation of biarylmethanes. This method involves the initial formation of biarylmethanols via reaction of aryl Grignards with carbonyl compounds followed by a subsequent reduction with iodotrimethylsilane (TMSI). A number of improvements over existing literature procedures are reported as well as previously unobserved dimerizations. Studies reveal that as few as 3 equiv of TMSI will give complete reduction in most cases where either of the substituents are not heteroaromatic. Mono-substituted alkanois react with TMSI to afford the corresponding iodides. A mechanistic study of the TMSI reduction is also reported.