A Route to “all-cis” 2-Methyl-6-Substituted Piperidin-3-ol Alkaloids from syn-(2R,1′S)-2-(1-Dibenzylaminomethyl)epoxide: Rapid Total Synthesis of (+)-Deoxocassine

Crystallization-Induced Diastereomer Transformation of α-Bromo α'-Sulfinyl Ketones. Diastereodivergent Synthesis of (+)-α-Conhydrine and (-)-β-Conhydrine

Crystallization-Induced Diastereomer Transformation (CIDT) of α-bromo-α'-(R)-sulfinylketones is reported. This process provides not readily accessible enantiopure stereolabile α-bromoketones, which after diastereoselective carbonyl group reduction lead to the corresponding highly value-added anti and syn-bromohydrins with excellent diastereoselectivities. As an application, a diastereodivergent synthesis of enantiopure hemlock alkaloid (+)-α-conhydrine and its diastereomer (-)-β-conhydrine is also described.