Sodium triethylborohydride as a catalyst for the dehydrogenative silylation of terminal alkynes with hydrosilanes

The first example of sodium triethylborohydride-catalyzed C(sp)-H bond silylation is reported. The reaction of aromatic and aliphatic alkynes with aromatic hydrosilanes and hydrosiloxanes proceeded in a highly selective manner to afford dehydrocoupling products. Competitive hydrosilylation of the terminal alkyne did not occur as a side-reaction. In view of the above it is remarkable that NaHBEt3 is commonly used as a reducing agent generating active transition-metal catalysts in situ in other hydrosilylation reactions.