Temporary Silicon Connection Strategies in Intramolecular Allylation of Aldehydes with Allylsilanes
作者:Julien Beignet、Peter J. Jervis、Liam R. Cox
DOI:10.1021/jo800824x
日期:2008.7.1
dimethylsilyl ether connection between the aldehyde and allylsilane, with a range of Lewis and Brønsted acid activators provides an (E)-diene product. The mechanism of formation of this undesired product is discussed. Systems containing a sterically more bulky diethylsilyl ether connection react differently: thus in the presence of TMSOTf and a Brønsted acid scavenger, intramolecular allylation proceeds
Diastereoselective Oxidative Carbon−Carbon Bond Formation via Silyl Bis-enol Ethers
作者:Christopher T. Avetta、Leah C. Konkol、Carla N. Taylor、Karen C. Dugan、Charlotte L. Stern、Regan J. Thomson
DOI:10.1021/ol802516z
日期:2008.12.18
Diisopropylsilyl bis-enol ethers are shown to be powerful intermediates for the diastereoselective dimerization and cross-coupling of cyclic ketones. The trends observed for the oxidative coupling of a range of different dialkylsilyl bis-enol ethers derived from cyclohexanone are rationalized by invoking a stereochemical model based on a Thorpe-Ingold effect.