Observations on the synthesis of photochromic naphthopyrans

…, AC Instone, DA Thomas, SM Partington…

Index: Gabbutt, Christopher D.; Heron, B. Mark; Instone, Alicia C.; Thomas, David A.; Partington, Steven M.; Hursthouse, Michael B.; Gelbrich, Thomas European Journal of Organic Chemistry, 2003 , # 7 p. 1220 - 1230

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Citation Number: 43

Abstract

Abstract 1-Naphthol reacts with 1, 1-diarylprop-2-yn-1-ols 5a, b, under alumina catalysis, by two pathways to give the photochromic naphtho [1, 2-b] pyrans 6a, b, together with the propenylidenenaphthalenones 7a, b, representatives of a new class of merocyanine dyes. With 2-methyl-1-naphthol, formation of the photochrome is suppressed; the only products are merocyanines 7c, d. The cyclocondensation of 2-naphthol with 5a, b proceeds much ...