An Improved Synthesis of Hydroxyindoles

Abstract

An improved synthetic procedure for the synthesis of 6- and 7-hydroxyindoles is described. In this method, the addition of two chlorine atoms in 1-benzyloxy-4,5-dichloro-2-nitrobenzene (3) and 1-benzyloxy-2,6-dichloro-3-nitrobenzene (9) facilitated the subsequent cyanomethylation step to give substituted cyanomethyl-dichloronitrobenzenes 4 and 10, leading to an overall increase in the yield of the hydroxyindoles 6 and 12.

Key words

indole synthesis - hydroxyindoles - cyanomethylation

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