Synthesis of optically active 1-t-butyl-4-ethylidenecyclohexane via CO2-elimination from a spirofused β-lactone
摘要:
(R)-1-t-Butyl-4-ethylidene cyclohexane (R)-1) is prepared with >98% ee from 4-t-butylcyclo-hexane carboxylic acid via the optically active beta-lactone 10.
Asymmetric Construction of 4<i>H</i>-Carbazol-4-one Intermediates via the Cyclohexadienone Annulation of Chiral Carbene Complexes
作者:John F. Quinn、Timothy S. Powers、William D. Wulff、Glenn P. A. Yap、Arnold L. Rheingold
DOI:10.1021/om970639k
日期:1997.11.1
The quaternary carbon in a 4H-carbazol-4-one can be introduced with high stereoprecision in the cyclohexadienone annulation of a 2-indolyl chromium carbenecomplex bearing an imidazolidinone chiral auxiliary. The chiral complex 12 was found to exist as atropisomers that were readily separated, and each was found to react with the same alkyne to give opposite configurations at the quaternary carbon
(R)-1-t-Butyl-4-ethylidene cyclohexane (R)-1) is prepared with >98% ee from 4-t-butylcyclo-hexane carboxylic acid via the optically active beta-lactone 10.