Unexpected catalytic activity of simple triethylborohydride in hydrosilylation of alkenes
The first example of sodium triethylborohydride-catalysed hydrosilylation of alkenes is reported. The hydrosilylation of certain alkenes, in particular styrenes, vinylsilanes and allyl glycidyl ether, with aromatic hydrosilanes proceeded in a highly regioselective manner to give Markovnikov products. It is significant that several protocols use NaHBEt3 as reducing agent generating active catalysts in situ of other hydrosilylation reactions. An anionic mechanism of hydrosilylation is proposed.