Regiospecific Baeyer-Villiger Oxidation of α,α-Dichlorocyclobutanones: A Norbisabolide γ-lactone Analogue1
摘要:
Details and methodological comparisons are presented on the preparation of a norbisabolide gamma-lactone analogue (4) via dichloroketene cycloaddition to limonene followed by regioselective Baeyer-Villiger oxidation (CH3CO3H) of the alpha,alpha-dichlorocyclobutanones 3 and C-Cl reduction (Zn/HOAc). The sequence of reduction followed by oxidation (HOCl) applied to 3 produced 4 in much better yield.
Regiospecific Baeyer-Villiger Oxidation of α,α-Dichlorocyclobutanones: A Norbisabolide γ-lactone Analogue1
摘要:
Details and methodological comparisons are presented on the preparation of a norbisabolide gamma-lactone analogue (4) via dichloroketene cycloaddition to limonene followed by regioselective Baeyer-Villiger oxidation (CH3CO3H) of the alpha,alpha-dichlorocyclobutanones 3 and C-Cl reduction (Zn/HOAc). The sequence of reduction followed by oxidation (HOCl) applied to 3 produced 4 in much better yield.
Free radical annulation of dichlorocyclobutanones with sequential ring expansion
作者:Paul Dowd、Wei Zhang、Steven J. Geib
DOI:10.1016/0040-4020(95)00093-n
日期:1995.3
reaction of dichloroketene with 1,5-dienes undergo intramolecular freeradical annulation. Lewis acid-promoted ring-opening of the cyclized cyclobutanones then yields novel ringexpansion products. Reaction of (R)-carvone provides an unusual example leading to the formation of a tricyclic dione. The carbonyl group of carvone enhances the radical cyclization and influences the ring-opening pathway.