Anti-carbometalation of homopropargyl alcohols and their higher homologues via non-chelation-controlled syn-carbometalation and chelation-controlled isomerization

A novel method for net anti-carbometalation of homopropargyl alcholols is described. The scheme is based on the study which shows that syn- and stereorandom-carboalumination products from sigma-hydroxyalkynes can be thermally isomerized to form alkenylalanes that correspond to anti-carboalumination of alkynes. The conditions and mechanisms for the reactions are presented.