Syntheses and Photochromism of Diaza [ 3 ] (9, 10) anthraceno[ 3 ] (1, 4)-naphthalenophane and Diaza [3. 3] (9, 10) anthracenophanet

Abstract

Diazaanthracenonaphthalenophane 2 and diazaanthracenophane 3 with trifluoroacetyl group on their nitrogen atom were newly synthesized. The electronic spectra and reactivities of 2 and 3 were compared with those of diazaanthracenoparacyclophane 1 which was previously reported by ourselves. Compounds 2 (yellow and nonfluorescent) and 3 (red and nonfluorescent)underwent the photocyclization similarly to 1 (greenish yellow and fluorescent). Quanturn yields of the photocyclization of both 2 and 3 were about O.5, twice as much as that of 1 (Table 2). The photoreaction of 1 was quenched by oxygen, while those of 2 and 3 were not quenched (Table 2). The original compound 2 was recovered more slowly by heating the photoproduct of 2 than similar reaction related to 1 (Figs.3 and 4, and Table 2). On the other hand, 3 was not recovered by heating the photoproduct of 3 (Fig.5). Interestingly 3 underwent a novel ( 4π+4π ) thermal dimerization (cyclization) (Fig.8 and Table 2).