Rhodium-Catalyzed -Bis-Silylation Reactions of 2-Ethynyl-3-pentamethyldisilanylpyridines.

Rhodium-catalyzed reactions of 2-ethynyl-3-pentamethyldisilanylpyridine derivatives ( and ) are reported. The reactions of compounds and in the presence of catalytic amounts of rhodium complexes at 110 °C gave the corresponding pyridine-fused siloles () and () through intramolecular -bis-silylation cyclization. The reaction of 2-bromo-3-(1,1,2,2,2-pentamethyldisilanyl)pyridine with 3-phenyl-1-propyne in the presence of PdCl(PPh)-CuI catalysts afforded 1:2 bis-silylation adduct . DFT calculations were also performed to understand the reaction mechanism for the production of compound from compound .