Palladium-Catalyzed Silylation of 2,3-Allenols with Unactivated Disilanes: Access to 2-Silyl-1,3-butadienes and α-Silyl-β-hydroxy Vinylsilanes

Regioselective silylation of 2,3-allenols with disilanes was carried out under catalysis of Pd(2)dba(3)/P(o-MeOC6H4)(3). In the presence of Cs2CO3, the reaction achieved 2-silyl-1,3-dienes. Reaction of 1-aryl-2,3-allenols gave the products with excellent Z/E selectivity and E-isomers as the major species. Reaction of alpha-alkylallenols or alpha-alkyl-alpha-aryl-allenols resulted in products with moderate Z/E selectivity and E-isomers are also major. Without a base, the reaction produced alpha-silyl-beta-hydroxyl vinylsilanes, which were converted to 2-silyl-1,3-dienes upon treatment with Cs2CO3.

Automated summary

Regioselective silylation of 2,3-allenols with disilanes was achieved under the catalysis of Pd(2)dba(3)/P(o-MeOC6H4)(3). The presence of Cs2CO3 led to the formation of 2-silyl-1,3-dienes. The reaction showed different selectivities and major isomers depending on the substrate used.