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[摘要]:A straightforward synthesis of fully substituted beta-carbolines via Bronsted acid promoted cyclizations of alpha-indolyl propargylic alcohols with nitrones is described. The use of nitrones bearing alkenyl or electron-rich aryl groups as the R-4 substituent dramatically switches the reaction pathway to afford tetrasubstituted alkenes and amines, which is assumed to proceed through a rearrangement reaction involving N-O bond cleavage and 1,2-migration of the R-4 group to an adjacent nitrogen atom, |
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