Quinone platinum complex catalyzed hydrosilylation of alkenes and alkynes

The (bisvinyl)siloxane 2-methyl-1,4-naphthoquinone platinum complex 1 catal yzes the hydrosilylation of styrenes 2a-e with triethylsilane. The beta -si lyl regioisomers are formed as major products along with minor amounts of o l-isomers and E-beta -silyl styrenes. Depending on the styrene substitution pattern, the turnover numbers range between 553 and 973. Trimethylvinylsil ane undergoes regioselective beta -silylation in good yields. A 8:1 regiopr eference in favor of the beta -silyl addition product is observed for 1-pen tyne. (C) 2000 Elsevier Science B.V. All rights reserved.