Nine 4,4-disubstituted-1,1-dimethoxycyclohexanes have been synthesized. The 4-geminal substituents are: methyl-neopentyl, methyl-cyclohexyl, methyl-benzyl, methyl-vinyl, methyl-phenyl, methyl-chloromethyl, methyl-dichloromethyl, methyl-trichloromethyl, and isopropyl-phenyl.
Enantioselective Conversion of Achiral Cyclohexadienones to Chiral Cyclohexenones by Desymmetrization
作者:Yixin Han、Simon Breitler、Shao-Liang Zheng、E. J. Corey
DOI:10.1021/acs.orglett.6b03186
日期:2016.12.2
The enantioselective reduction of prochiral 4,4-disubstituted 2,5-cyclohexadienones to chiral 2-cyclohexenones has been accomplished by the use of a carefully selected chiral bisphosphine–CuI complex and diisobutylaluminum hydride–hexamethylphosphoric triamide complex. This reagent has provided access to a key bicyclic intermediate for the totalsynthesis of the natural enantiomer of the pentacyclic