Inversion of Diastereoselectivity Depending on Substrate Concentration in Baker’s Yeast Catalyzed Reduction of σ-Symmetrical 1,3-Cyclopentadiones and 1,3-Cyclohexadiones
Enolate Generation under Hydrogenation Conditions: Catalytic Aldol Cycloreduction of Keto-Enones
作者:Ryan R. Huddleston、Michael J. Krische
DOI:10.1021/ol0300219
日期:2003.4.1
[GRAPHIC]Formal heterolytic activation of elemental hydrogen under Rh catalysis enables the reductive generation of enolates from enones under hydrogenation conditions. Enolates generated in this fashion participate in catalytic C-C bond formation via carbonyl addition to aldehyde and, as demonstrated in this account, ketone partners. Notably, the use of appendant dione partners enables diastereoselective formation of cycloaidol products possessing 3-stereogenic centers, including 2-contiguous quaternary centers.