Hydrosilylation of 1,4-bis(trimethylsilyl)-1-buten-3-ynes using late transition metal hydrides as catalyst precursors

Two geometrical isomers of 1,4-bis(trimethylsilyl)-1-buten-3-yne (cis- and trans-1) were subjected to catalytic hydrosilylation with HSiR3 (HSiMe2Ph or HSiMePh2) in the presence of catalytic amounts of late transition metal hydrides. Four kinds of regio- and stereoisomers of hydrosilylation products were formed: (R3Si)(Me3Si)CCCHCH2SiMe3 (2), (1Z,3E)-CH(SiMe3)C(SiR3)CHCHSiMe3 (3), (1Z,3E)-C(SiMe3)(SiR3)CHCHCHSiMe3 (4), and (1E,3E)-C(SiMe3)(SiR3)CHCHCHSiMe3 (5). The product selectivity was strongly affected by the geometry of 1 as well as the catalyst precursor employed. Compounds 2–5 could be prepared in over 93% selectivity, respectively.