Photochemische Cycloadditionen von 3‐Phenyl‐2<i>H</i>‐azirinen mit Triphenyl‐vinylphosphoniumbromid. 36. Mitteilung über Photoreaktionen

Abstract

Abstract On irradiation in acetonitrile 3‐phenyl‐ 2H ‐azirines of type 1 react with triphenyl vinyl phosphonium bromide to form in approximative 50% yield 2H ‐indoles of type 4 (Scheme 1) . In analogy to other photochemical reactions with 2H ‐azirines [2] [3] it is assumed that the photochemically generated dipoles 2 react with the triphenyl vinyl phosphonium salt (Scheme 1) . The conversion of 1 to 4 represents a new synthesis for 2H ‐pyrroles.