On the [42] Cycloaddition Approach to Indolo [2, 3-a] carbazoles

JF Barry, TW Wallace, NDA Walshe

Index: Barry, John F.; Wallace, Timothy W.; Walshe, Nigel D. A. Tetrahedron, 1995 , vol. 51, # 47 p. 12797 - 12806

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Citation Number: 41

Abstract

2, 2′-Biindolyl 9 reacts with electron-deficient dienophiles at 100–110° C to give low to moderate yields of Michael addition and formal [42] cycloaddition products, with the former predominant; the products derived from 9 and 2-(phenylsulphinyl) maleimides 14 and 15 undergo in situ elimination of benzenesulphenic acid, leading to 2, 2′-biindolylsubstituted maleimides which can be efficiently photocyclised into indolo [2, 3-a] carbazoles.