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US 4,785,128 AGranted
Process for the preparation of bis-styrylbenzenes
AssigneeCiba-Geigy Corporation
InventorLeonardo Guglielmetti
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AssigneeCiba-Geigy Corporation
InventorLeonardo Guglielmetti
Estimating the term…
A fluorescent brightener is proposed which consists of 51-99% of an unsymmetrically substituted compound of the formula ##STR1## in which R and R.sub.1 are identical or different and, if R and R.sub.1 are identical, R.sub.1 must occupy a position in the phenyl ring to which it is bonded which differs from the position occupied by R in its phenyl ring, and in which R and R.sub.1 independently of one another are CN or a carboxylic acid ester group, and 49-1% of a symmetrically substituted compound of the formula ##STR2## in which R is as defined above and the two R's are bonded to identical positions in their phenyl rings, as are also agents which contain these fluorescent brighteners and the use of these fluorescent brighteners for the fluorescent brightening of, in particular, textile materials, preferably made of polymer. The said fluorescent brighteners are prepared by reacting terephthalaldehyde preferably with a correspondingly substituted benzylphosphonate and further reacting the resulting mixture of a correspondingly substituted 4-stilbene aldehyde and a symmetrical p-bis-styrylbenzene with a benzylphosphonate which differs from the benzylphosphonate first used.
A process for the preparation of a fluorescent brightener consisting of (a) 51 to 99% of an unsymmetrically substituted compound of the formula ##STR55## in which R and R.sub.1 are identical or different and, if R and R.sub.1 are identical, the substituent positions of R and R.sub.1 must be different, and in which R and R.sub.1 independently of one another are CN or a carboxylic acid ester group and (b) 49 to 1% of a symmetrically substituted compound of the formula ##STR56## in which R is as defined above and the two Rs are bonded to identical positions of their phenyl rings, which comprises reacting terephthalaldehyde with a compound of the formula ##STR57## to give a mixture of the compounds of the formulae ##STR58## and then further reacting this mixture with a compound of the formula ##STR59## to yield the fluorescent brightener wherein X and Y are identical or different and independently of one another are (a) hydrogen, (b) a radical of the formula --COOZ in which Z is alkyl or (c) a radical of the formula --ZnBr, --ZnCl, --MgBr, --MgCl, ##STR60##
A process for the preparation of an unsymmetrically substituted optical brightener compound of the general formula ##STR76## where R and R.sub.1 independently of one another are cyano, or C.sub.1-6 alkoxycarbonyl, and free of p,p'-substituted compounds, which comprises reacting in a first step terephthaladehyde with a phosphonate compound of the general formula IIa ##STR77## or of the general formula IIb ##STR78## where R and R.sub.1 have the above meanings in the presence of an alkali, in a solvent from which the monocondensation product of terephthaldehyde and the phosphonate compound precipitates to form a first reaction product containing the monocondensation product and thereafter completing the reaction to prepare a compound of formula (I) by reacting the first reaction product in the presence of alkali and an inert solvent with a different phosphonate compound of formula IIa or IIb, with the proviso that at least one compound of formula IIa and a compound of formula IIb are reacted successively in the process.
A process for the preparation of a fluorescent brightener consisting of 51 to 99% of an unsymmetrically substituted compound of the formula ##STR79## in which R and R.sub.1 are identical or different, and, if R and R.sub.1 are identical the substituent positions of R and R.sub.1 must be different, and in which R and R.sub.1 independently of one another are CN or a carboxylic acid ester group, and 49-1% of a symmetrically substituted compound of the formula ##STR80## in which R is as defined above and the two R's are bonded to identical positions of their respective phenyl rings, which comprises, in a first stage, reacting terephthalaldehyde with a compound of the formula ##STR81## in the presence of dimethylformamide as solvent to give a mixture of the compounds of the formulae ##STR82## and then reacting said monoaldehyde-containing mixture obtained in the first stage without isolation with a compound of the formula ##STR83## wherein X and Y are identical or different and independently of one another are hydrogen or a radical of the formula --COOZ, in which Z is alkyl;
Dependencies are inferred from the claim text.