2005

Carbazole derivativesR 0150 A New Preparative Route to Substituted Carbazoles by Benzannulation. — A

novel method for the synthesis of substituted carbazoles (X) is developed starting from readily available o-iodoanilines (I). The key intermediates (VIII) are prepared by So-nogashira coupling of N-tosyl derivatives (III) with propargyl alcohol (IV) followed by oxidation and subsequent Wittig reaction of the aldehyde (VI). The formation of both the heterocyclic ring and the aromatic ring in carbazoles (X) is achieved by a regiospe-cific benzannulation of the acids (VIII) in Ac2O. — (SERRA*, S.; FUGANTI, C.; Synlett 2005, 5, 809-812; Ist. Chim. Ric. Mol. Sez., Dep. Chim. Mater. Ing. Chim. Politec., I-20133 Milano, Italy; Eng.) — R. Staver

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