Bisbenzoxazolyl stilbenes and their use as fluorescent brightening agents

摘要

The invention comprises a compound of formula in which R1 represents one or more substituntes which may be halogen atoms, alkyl, aryl, alkanyl, arylalkyl, alkoxy, aryloxy, acyl, acyloxy, hydroxyl, amino, substituted amino, quaternized ammonium, sulpho, substituted sulphonyl, sulphamyl, substituted sulphamyl, cyano, thiocyano, thiol, carbamyl, substituted carbamyl, carbamyloxy or nitro groups, and Y and Y1 each represent a hydrogen atom, alkyl, aryl or cyano group which are fluorescent brightening agents and which are prepared by heating a 4,41-bis-(2-hydroxy-phenyl carbamoyl) stilbene at from 200 DEG to 400 DEG C. These compounds are prepared in turn by reacting a 4,41-stilbene dicarboxylic acid chloride with an o-aminophenol in the presence of a solvent. Examples describe the preparation of 4,41-bis-benzoxazol - 2 - yl) - stilbene, 4,41 - di - (benzoxazol - 2 - yl) - 2 - methylstilbene, 4,41 - di-(benzoxazol - 2 - yl) - a - cyanostilbene, 4,41-di-(benzoxazol - 2 - yl) - 2,21 - dimethylstilbene, 4,41 - di - (6 - methoxybenzoxazol - 2 - yl)-stilbene, 4,41 - di - (benzoxazol - 2 - yl) - 2-nitrostilbene, 4,41 - di - (benzoxazol - 2 - yl)-2 - aminostilbene, 4,41 - di - (benzoxazol - 2 - yl)-2 - hydroxystilbene, 4,41 - di - (benzoxazol - 2-yl)-2 - chlorostilbene, 4,41 - di - benzoxazol - 2 - yl)-2 - cyanostilbene, 4,41 - bis - (6 - chlorobenzoxazol - 2 - yl) - stilbene, 4,41 - bis - (6 - methylsulphonylbenzoxazol) - 2 - yl) - stilbene, 4,41-bis - (5 - cyanobenzoxazol - 2 - yl) - stilbene and many other compounds are specified.