versatile chiral building block. The strategy is based on three key transformations: enantioselective hetero-Diels−Alder (HDA) reaction of aldehyde with Danishefsky’s diene, selective reduction of carbonyl function, and Claisen or related rearrangement. The synthetic utility of the methodology is illustrated by totalsynthesis of antibiotic (−)-centolobine.
A Ring Expansion─Stereoselective Cycloaddition of Carbohydrate-Derived Donor–Acceptor Cyclopropanes: Synthesis of Bridged Oxepanone–Indole Hybrids
作者:M V Kamala Lakshmi、Intzar Ali、Ramu Sridhar Perali
DOI:10.1021/acs.joc.2c01652
日期:2022.9.16
investigated. The reaction condition is optimized by monitoring the progress at various temperatures, with various solvents, and with different Lewis acid catalysts. Under optimized conditions, high stereoselectivity and efficiency are achieved in most of the formed cycloadducts. The accessibility of the strategy is evaluated by utilizing an array of carbohydrate-derived donor–acceptorcyclopropanes and variably