Access to fused nitrogen heterocycles via Diels- Alder reactions of pyrrole with maleimide

Abstract

Nitrogen heterocyclic chemistry is attractive because of its potential impact in the form of both natural and synthetic products. Fused pyrrole rings in particular have shown the potential for anti-cancerous activity upon placement in the human body. Recently, many have been interested in increasing the efficiency of this family of reactions in order to not only create molecules with biological activity, but create them with high yield for potential industrial use. Herein, we report the synthesis of a fused pyrrole diene for further cyclization with maleimide with the intention of forming a biologically active Diels-Alder adduct in high yield. Decarboxylation with sodium hydroxide to form the fused ketone has been performed in good yield. This scheme can be applied generally to form useful diene products from cheap and plentiful starting materials that have the potential to create a positive medical effect. Future efforts will be focused on fused rings of varying size as well as the addition of substituted maleimide derivatives using a similar methodology described.