Synthetic Approaches to Highly Functional β-Carboline Building Blocks via Allylic Amidation

Abstract

A new, straightforward synthesis of highly functional β-carboline building blocks is presented that makes use of allylic amidation methodology. The products obtained carry a terminal double bond as well as an easy-to-deprotect amide, which make them perfectly suitable for further functionalization. The use of the trifluoroacetamide group is exploited in a dual fashion; it acts as a protecting group and functions as the nucleophile for the allylic amidation reaction.

Key words

indoles - β-carbolines - allylic amidation - heterocycles - Stille reaction

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25

N-Benzyltryptamine 7b could also be trapped with acrolein after lithiation to give secondary allylic alcohol 12 (Scheme 6). See the experimental section for details.

Scheme 6