74970-67-5Relevant articles and documents
B(C6F5)3 catalyzed hydrosilation of enones and silyl enol ethers
Blackwell, James M,Morrison, Darryl J,Piers, Warren E
, p. 8247 - 8254 (2007/10/03)
The 1,4 hydrosilation of a variety of simple α,β-unsaturated enones as catalyzed by B(C6F5)3 (1-2%) is described. For substrates with no steric hindrance near the β-carbon, 1,4 addition of silane is very clean; in other instances, 1,2 hydrosilation is competitive. The reaction is facile with five commercially available silane reagents. For two examples, a novel hydrosilation of the resulting silylenol ethers was also observed. The net trans stereochemistry of H-Si addition to the silylenol ether C=C bond was established and points to a stepwise mechanism for this reaction. This was supported by the observation and full spectroscopic characterization of a silylcarboxonium ion intermediate with an [HB(C6F5)3]- counteranion in the hydrosilation of the silylenol ether derived from 4,4-dimethyl-2-cyclohexen-1-one and PhMe2SiH.
The Scope and Limitations of Intramolecular Radical Cyclizations of Acylsilanes with Alkyl, Aryl, and Vinyl Radicals
Chang, Sheng-Yueh,Jiaang, Weir-Torn,Cherng, Chaur-Donp,Tang, Kuo-Hsiang,Huang, Chih-Hao,Tsai, Yeun-Min
, p. 9089 - 9098 (2007/10/03)
5-Exo cyclizations of primary and secondary radicals with acylsilanes successfully give cyclopentyl silyl ethers. The corresponding 6-exo cyclizations are sensitive to changes of the size of silyl groups. Secondary radicals undergo 6-exo cyclizations with
