The intramolecular capture of thermally generated merocyanine dyes derived from naphthopyrans: Photochromism of 5-(diarylhydroxymethyl)-2H-naphtho[1,2-b] pyrans

Christopher D. Gabbutt, Lucy V. Gibbons, B. Mark Heron, Suresh B. Kolla

Research output: Contribution to journalArticle

5 Citations (Scopus)


A series of 2H-naphtho[1,2-b]pyrans bearing a diarylmethanol unit at C-5 have been synthesised by the addition of an excess of an aryllithium reagent to alkyl 2H-naphtho[1,2-b]pyran-5-carboxylate precursors. These naphthopyrans show photochromism when exposed to ultraviolet irradiation and also generate intense colours at low pH through triarylmethine cation generation. However, photochromism of the triarylmethine cation derived from the naphthopyran unit could not be detected. An irreversible cascade process initiated by the thermally-induced ring-opening of the diarylmethanol substituted 2H-naphtho[1,2-b]pyrans in the presence of an acid catalyst afforded novel benzopentalenonaphthalenone dyes.

Original languageEnglish
Pages (from-to)995-1004
Number of pages10
JournalDyes and Pigments
Issue number3
Publication statusPublished - 1 Mar 2012
Externally publishedYes


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