Indium(III) Chloride-Promoted Rearrangement of Epoxides: A Selective Synthesis of Substituted Benzylic Aldehydes and Ketones
摘要:
A simple and efficient procedure for the rearrangement of substituted epoxides catalyzed by InCl3 has been developed. Aryl-substituted epoxides isomerize with complete regioselectivity to form a single carbonyl compound via cleavage of the benzylic C-O bond. The reactions are simple, fast, and high yielding. This procedure is very mild compared to those catalyzed with BF3 and other Lewis acids and compatible with several acid-sensitive functionalities. This protocol provides a highly selective synthesis of substituted benzylic aldehydes and ketones. However, rearrangement of alkyl-substituted epoxides is not very selective.
realized. Remarkably, by using a different copper precursor, the aldehydes obtained can be further hydrogenated to give the corresponding alcohols under the same conditions, formally named as hydroxymethylation of alkenes. Under pressure of syngas, various aldehydes and alcohols can be produced from alkenes with copper as the only catalyst, in excellent regioselectivity. Additionally, an all-carbon quaternary
Indium(III) Chloride-Promoted Rearrangement of Epoxides: A Selective Synthesis of Substituted Benzylic Aldehydes and Ketones
作者:Brindaban C. Ranu、Umasish Jana
DOI:10.1021/jo980793w
日期:1998.11.1
A simple and efficient procedure for the rearrangement of substituted epoxides catalyzed by InCl3 has been developed. Aryl-substituted epoxides isomerize with complete regioselectivity to form a single carbonyl compound via cleavage of the benzylic C-O bond. The reactions are simple, fast, and high yielding. This procedure is very mild compared to those catalyzed with BF3 and other Lewis acids and compatible with several acid-sensitive functionalities. This protocol provides a highly selective synthesis of substituted benzylic aldehydes and ketones. However, rearrangement of alkyl-substituted epoxides is not very selective.