The selective dehydrogenative coupling reaction between phenylsilane and ethynylbenzene occurred in the presence of some homogeneous base catalysts such as alkoxides, alkyl compounds, and the amides of alkali metals or barium. The order of the catalytic activities was Ba (OR) 2> LiN (SiMe3) 2∼ n-BuLi> LiOEt. Barium alkoxide showed the highest activity and selectivity for the reaction, and gave the polymer poly [( ...