Unusual bromination of tetrahydro-(–)-α-santonins and new santonin isomers: X-ray crystal and molecular structure of 2β,14-dibromo-4α,5β,6β,11βH-tetrahydrosantonin
Abstract
A novel bromination–dehydrobromination reaction of tetrahydro-(–)-α-santonins is reported which has led, via the 2α,14- and 2β, 14-dibromo ketones (2a,b), to two new dienone isomers of (–)-α-santonin whose structures were established by X-ray diffraction and c.d. studies of (2b).