Palladium-Catalyzed Dimerization−Carbostannylation of Alkynes:  Synthesis of Highly Conjugated Alkenylstannanes ShirakawaEiji YoshidaHiroto NakaoYoshiaki HiyamaTamejiro 1999 Palladium-Catalyzed Dimerization−Carbostannylation of Alkynes:  Synthesis of Highly Conjugated Alkenylstannanes