Process for the preparation of beta-Hydrosyalkylpicolinium salts and picolinium salts as intermediates for the prepation of cationic dyes

摘要

Preparation of beta -hydroxyalkylpicolinium salts of formula (I) comprises reacting a picoline compound of formula (II) with an alkylene oxide compound of formula (III) in the presence of a mono- to tri-basic acid. R1 = H, CN, 1-4C alkoxycarbonyl or optionally substituted 1-4C alkyl; R2, R3 = H, or 1-4C alkyl or phenyl (both optionally substituted); X = the residue of one equivalent of a mono- to tri-basic acid; and the ring A is optionally additionally substituted and/or condensed with carbocyclic or heterocyclic rings. The compounds (Ia) of formula (I) are new, provided X is not halide. Also claimed are (1) a process for preparing cationic dyestuffs (C) by reacting the products (I) or (Ia) with aromatic or heteroaromatic aldehydes; (2) dyestuff preparations (A) or (B) with a chloride content of less than 0.5 wt. %: where (A) contains at least one cationic dyestuff prepared from (I) obtained by the process, or (Ia); and (B) preferably has a chloride content of less than 0.1 wt. %, and contains a cationic dyestuff and beta -hydroxyalkyl hydrogen sulphate (preferably beta -hydroxyethyl hydrogen sulphate (IV)).