Highly regioselective platinum catalyzed hydrometallation of propargylic alcohols

A Pt catalysed hydrometallation reaction has been developed that provides b-metallated products as a single region and geometric isomer. The reaction is incredible tolerant of sterics and actually performs better in more sterically congested stubstrates. We have demonstrated this approach in hydrosilylations, hydrostannylations and hydroboronations. We have shown a wide range of silanes to participate in this reactions and a Denmark type one-pot hydrosilylation-Hiyama coupling has been achieved as a single regioisomer. The regioselectivity has been probed for internal alkynes and we have discovered that the regioselectively is determined by both steric and electronic factors. We can selectively form either the a or b-products as a single regioisomer by altering the steric environment and we have discovered that electronic effects overide the sterics.