Patent GB-430499-A (GB)
Title: Improvements in or relating to the manufacture of new dyestuffs of the triarylmethane series
IPC: C09B11/12
Filed: 1933-12-20
Abstract: Triarylmethane dyes containing the group <FORM:0430499/IV/1> wherein R stands for hydrogen, alkyl, aralkyl, or aryl and "alk" stands for an alkyl group of at least two carbon atoms and containing at least one substituent are prepared by the following methods: (1) an aromatic amino sulphonic acid of the formula <FORM:0430499/IV/2> (wherein R and "alk" have the above significance) is condensed with a suitable aldehyde and the resulting leuco body oxidized to form the dye; (2) a triarylmethane dye containing a free amino group is condensed with an appropriate halogenalkylsulphonic acid; (3) a hydroxy substituent present in the alkyl group of a triarylmethane dye alkylated in an amino group is replaced by a sulpho group by transforming into the sulphonic acid ester and treating this with sulphite.  The products dye wool or silk in clear reddish-violet to blue to green shades.  In examples: (1) 1-n-butylphenylamino - 2 - oxypropane - 3 - sulphonic acid (prepared by condensing chlorohydroxypropane sulphonic acid with butylaniline) is condensed with o-chlorbenzaldehyde and the resulting leuco compound oxidized with chromic acid; it dyes animal fibre yellowish-green; (2) 1 - o - tolylamino - 2 - oxypropane - 3 - sulphonic acid (prepared by condensing chlorhydroxypropane-sulphonic acid with o-toluidine) is condensed with p-chlorbenzaldehyde and oxidized to give a bluish-green dye; the product is condensed with p-phenetidine to give a violet dye; (3) 1-n-butyl-m-tolylamino-2-oxypropane-3-sulphonic (prepared by condensing chlorhydroxypropane-sulphonic acid with butyl-m-toluidine) is condensed with p-diethyl-aminobenzaldehyde and the leuco compound oxidized to give a blue dye; (4) 1-benzylphenyl-amino - 2 - oxypropane - 3 - sulphonic acid (prepared by condensing chlorhydroxypropane-sulphonic acid with benzylaniline) is condensed with p-diethylaminobenzaldehyde and the leuco body oxidized with chromic acid; (5) the leuco compound from tetramethyldiaminobenzhydrol and 1 - n - butylphenylamino - 2 - oxypropane - 3-sulphonic acid is converted to the sulphuric ester in the usual manner and heated with sodium sulphite; (6) one molar proportion of tetraethyl - 4 . 4<1> - diamino - 3<11> - aminotriphenylmethane is condensed with one molar proportion of 1 - chloro - 2 - oxypropane - 3 - sulphonic acid. A sample has been furnished under Sect. 2 (5) of a dye prepared by condensing 1 - n - butylamino - 3 - methoxypropane - 2 - sulphonic acid (prepared by converting 1 - n - butylphenylamino - 2 - oxy - 3 - methoxypropane into the sulphuric acid ester by means of monohydrate and treating the latter with sodium sulphite) with o-chlorbenzaldehyde and oxidizing the product; it dyes green shades.  The Specification as open to inspection under Sect. 91 relates to the manufacture of the above triarylmethane dyes according to methods known per se and the examples comprises the further details: (a) instead of condensing the product of example 2 with p-phenetidine tetrahydro-a -naphthylamine is used to give a reddish-violet dye; (6) the tetramethyldiamino-benzhydrol of example 5 is condensed with 1 - a  - naphthylaminopropane - 2 . 3 - di-sulphonic acid and 1-diphenylamino-2-oxypropane-3-sulphonic acid and the leuco body oxidized in each case; the products dye blue shades.  This subject-matter does not appear in the Specification as accepted.