The first structural and spectroscopic characterisation of a ring-opened form of a 2 H -naphtho[1,2- b ]pyran: a novel photomerocyanine

Abstract

Heating 4-methoxy-1-naphthol with a 1,1-diarylprop-2-yn-1-ol gave the 2,2-diaryl-6-methoxy-2 H -naphtho[1,2- b] pyran together with the novel merocyanine, (E)-2-[3′,3′-bis(aryl)allylidene]-4-methoxynaphthalen-1(2 H)-one. Brief UV-irradiation of the pyran favoured the formation of the (Z)-merocyanine with longer irradiation and/or acidic conditions favouring the (E)-isomer. © Partner Organisations 2014.