Bioinspired cyclization of in situ generated γ-indolyl β,γ-unsaturated α-keto esters via an oxidative enamine process: facile approaches to pyrano[2,3-b]indoles

Abstract

A bioinspired cyclization of in situ generated γ-indolyl β,γ-unsaturated α-ketoesters with an oxoammonium salt via an oxidative enamine process has been developed. Under mild conditions, the reactions afforded pyrano[2,3-b]indoles, which are found in a wide range of bioactive compounds, in good yields (up to 86% yield).