Preparation and Absolute Configuration of SomeIris Essential Oil Constituents of the 5-methylsafranic-acid series
作者:Christian Chapuis、Karl H. Schulte-Elte
DOI:10.1002/hlca.19950780116
日期:1995.2.8
cyclization of (+)-(Z)-6 to (−)-trans-8a (Scheme 2), followed by a diastereoselective epoxidation to (+)-11 gave, via acid-catalyzed dehydration of the intermediate allylic secondary alcohol (−)-12, the same ester (+)-13a (Scheme 3), but with poor optical purity (13% ee), due to an initial rapid [1,2]-H shift. The absolute configuration of (−)-16a–c was confirmed by chemicalcorrelation with (−)-trans-19 (Scheme