Phosphonium compounds, a process for their preparation and a process for the preparation of asymmetrically substituted stilbene fluorescent brightening agents

Abstract

Phosphonium compounds of the formula (R).sub.3 P.sup..sym. --CH.sub.2 --X--CH.dbd.CH--R.sub.1 Y.sup..crclbar. in which R is preferably alkyl having 1 to 4 C atoms, cyclohexyl or phenyl, R.sub.1 is a substituted or unsubstituted aromatic radical, especially a phenyl radical, X is phenylene, 4,4'-biphenylene or 1,4- or 2,6-naphthylene and Y.sup..crclbar. is SO.sub.3.sup..crclbar., SO.sub.2.sup..crclbar. or COO.sup..crclbar., a process for their preparation and a process for the preparation of asymetrically substituted fluorescent brightening agents of the formula Z--CH.dbd.CH--X--CH.dbd.CH--R.sub.1 --Y.sup..crclbar. M.sup..sym. in which R.sub.1, X and Y.sup..crclbar. are as defined above, M.sup..sym. is a cation and Z is preferably a substituted or unsubstituted phenyl or 2-phenyl-triazol-4-yl radical, by reacting a bis-phosphonium compound of the formula ##STR1## in which Q.sup..crclbar. is an anion, with an aldehyde of the formula M.sup..sym. Y.sup..crclbar. --R.sub.1 --CHO and reacting the resulting intermediate with an aldehyde of the formula Z--CHO.

Dependencies are inferred from the claim text.