Diverse Fates of β-Silyl Radical under Manganese Catalysis: Hydrosilylation and Dehydrogenative Silylation of Alkenes
作者:Xiaoxu Yang、Congyang Wang
DOI:10.1002/cjoc.201800367
日期:2018.11
Manganese‐catalyzed hydrosilylation of alkenes has been underdeveloped for a long time. Herein, we describe a general, chemo‐ and regio‐ selective hydrosilylation of alkenes by using the Mn(CO)5Br catalyst with ample substrate scopes. Meanwhile, dehydrogenative silylation of aryl olefins can be selectively achieved upon the catalysis of dinuclear Mn2(CO)10. Mechanistic experiments revealed diverse
Well-defined NHC-rhodium hydroxide complexes as alkenehydrosilylation and dehydrogenative silylation catalysts
作者:Byron J. Truscott、Alexandra M. Z. Slawin、Steven P. Nolan
DOI:10.1039/c2dt31339a
日期:——
Alkene hydrosilylation and dehydrogenative silylation reactions, mediated by [Rh(cod)(NHC)(OH)] complexes (cod = 1,5-cyclooctadiene; NHC = N-heterocyclic carbene) are described. The study details a comparison of the catalytic activity and steric characteristics of four rhodium complexes bearing different NHC ligands. The novel [Rh(cod)(Ii-PrMe)(OH)] complex (Ii-PrMe = 1,3-diisopropyl-4,5-dimethylimidazol-2-ylidine) was designed to improve the reactivity of Rh(I)-hydroxides and proved to be a successful promoter of hydrosilylation and dehydrogenative silylation, displaying good stereo- and regiocontrol.
the mechanism of the hydrosilylation, Si–H oxidative addition reactions towards the dinuclear platina-β-diketone 1 have been explored. Reactions of 1 with 2-picolyl substituted hydrosilanes of the type N SiMe2H and N SiMeH N resulted in decomposition with the formation of platinum black, only. On the other hand, the analogous reaction with the 8-quinolyl substituted silane of the type N SiMeH N was