An Efficient Synthesis of 1-Methyl-4,5,6,7-tetrahydro-1H-pyrrolo[2,3-c]pyridine and Its N⁶-Substituted Analogues

Abstract

An efficient synthesis of 1-methyl-4,5,6,7-tetrahydro-1H-pyrrolo[2,3-c]pyridine hydrochloride was achieved using simple sodium borohydride reduction of 6-benzyl-1-methyl-1H-pyrrolo[2,3-c]pyridin-6-ium bromide as the key step followed by its debenzylation with hydrogen over palladium on carbon on a multigram scale. Similarly, a series of N⁶-substituted 1-methyl-1H-pyrrolo[2,3-c]pyridin-6-ium halides were synthesized and reduced with sodium borohydride, showing this method to be applicable for the synthesis of different N⁶-substituted 1-methyl-4,5,6,7-tetrahydro-1H-pyrrolo[2,3-c]pyridines.

Key words

heterocycles - cyclization - alkylation - reduction - hydrogenation

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