Diastereoselective functionalisation of benzo-annulated bicyclic sultams: Application for the synthesis of cis-2,4-diarylpyrrolidines

The cis-dibromination of unsaturated bicyclic bridgehead sultams 5a and 5b, and experiments designed to understand the cis-stereochemical outcome of these reactions, are described. In the case of 5b, a novel solvent dependent carbocation rearrangement occurs with the formation of 18b. cis-Dibromides...

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Bibliographic Details
Main Authors: Susan Kelleher, Pierre-Yves Quesne, Paul Evans
Format: Article
Language:English
Published: Beilstein-Institut 2009-11-01
Series:Beilstein Journal of Organic Chemistry
Subjects:
Online Access:https://doi.org/10.3762/bjoc.5.69
Description
Summary:The cis-dibromination of unsaturated bicyclic bridgehead sultams 5a and 5b, and experiments designed to understand the cis-stereochemical outcome of these reactions, are described. In the case of 5b, a novel solvent dependent carbocation rearrangement occurs with the formation of 18b. cis-Dibromides 13a and 13b undergo regioselective dehydrobromination, and the participation of the resultant vinyl bromide 24a in lithiation and Pd-coupling chemistry is described. In the case of the latter, hydrogenation of the styryl products afforded a single diastereoisomer. These compounds were then studied under dissolved metal reduction conditions, in which the cleavage of both N–S and C–S bonds takes place to afford cis-2,4-diaryl-substituted pyrrolidines 35–37.
ISSN:1860-5397