Silylene [PSiP] Pincer Cobalt(II) Chloride–Catalyzed Alkene Hydrosilylation

ABSTRACT Silylene metal complexes exhibit excellent catalytic activity and selectivity in homogeneous catalysis. However, there are relatively few examples of silylene metal complexes as catalysts for the hydrosilylation of alkenes. In order to study the effect of a silylene ligand on the catalytic performance of [PSiP] pincer Co(II) chloride for alkene hydrosilylation, the PMe 3 ligand in (Me Si (C 6 H 4 ‐ P Ph 2 ) 2 )Co ( P Me 3 ) Cl ( 1 ) was replaced by a silylene ligand, and a silylene [PSiP] pincer Co(II) chloride, (Me Si (C 6 H 4 ‐ P Ph 2 ) 2 )Co (PhC (N t Bu) 2 Si ) Cl ( 2 ), was used as catalyst to study its catalytic activity in alkene hydrosilylation. It was confirmed that silylene Complex 2 has excellent catalytic activity for alkene hydrosilylation with Ph 2 SiH 2 as a hydrogen source. For alkene hydrosilylation, compared to phosphine Complex 1 , silylene Complex 2 does not need NaBHEt 3 as an additive. In addition, for aromatic alkenes, silylene Complex 2 has anti ‐Markovnikov selectivity, while phosphine Complex 1 provides Markovnikov products in the presence of NaBHEt 3 .