1,5-diaryl-3-styryl-2-pyrazoline cpds used - as optical brighteners

摘要

2-pyrazoline cpds. used as optical brighteners. Cpds. of formula:- (where R and R' are opt. subst. aryl, pref. phenyl, particularly p- chlorophenyl and X is vinyl or -CH2-CH2-Y, and Y is residue of hydrogen-active group) are obtained by condensing dibenzal cpds. of formula R-CH=CH-CO-CH=CH-R' at 60-130 degrees C with 4-hydrazino-phenyl-beta-hydroxyethylsulphone, opt. converting styryl pyrazolines obtained to mineral acid ester, opt. converting these to vinylsulphone cpds. and opt. adding to them hydrogen-active cpds. of formula H-Y.