Patent GB-660196-A (GB)
Title: Manufacture of new monoazo-dyestuffs
IPC: C09B29/30
Filed: 1948-09-09
Abstract: Compounds of the general formula <FORM:0660196/IV (b)/1> (wherein R1 represents an aromatic nucleus of the benzene series and R2 an aliphatic hydrocarbon radical of 8-12 carbon atoms) are manufactured by condensing a compound RSO2X (wherein R represents an aromatic nucleus of the benzene series and X a halogen atom or a reactive residue) with an amine H2N-R2, introducing into the nucleus R (if not already present therein) a substituent convertible into -NH2, and then so converting this substituent.  Thus the compound RSO2X may be a benzene sulphonic acid halide containing a nitro group, subsequently reduced (e.g. with iron and hydrochloric acid), or an acylamino group, subsequently hydrolysed, and the condensation may be effected in an anhydrous or aqueous medium, advantageously in the presence of an acid-binding agent (e.g. a tertiary base such as pyridine).  The nucleus R in the starting material may contain further substituents (e.g. halogen atoms such as chlorine, or alkoxy groups such as ethoxy or especially methoxy), or additional substituents may be introduced after the condensation, or substituents already present may be replaced by others.ALSO:Monoazo dyestuffs are manufactured by coupling a diazo compound of an amine of the general formula <FORM:0660196/IV (c)/1> wherein R1 represents an aromatic nucleus of the benzene series, which may contain further substituents (e.g. halogen atoms or alkoxy groups) and R2 represents an aliphatic hydrocarbon radical of 8-12 carbon atoms, with a naphthalene coupling component containing a nuclear sulphonic acid group and a nuclear hydroxy group, and free from aliphatic radicals of more than 9 carbon atoms.  Suitable components are on the one hand 3- or 4-amino-, 4-alkoxy-3-amino-, 3-alkoxy-4-amino-, 6-chloro-3-amino- and 4- or 6-methyl-3-amino-benzene-1-sulphonalkylamides (in which the alkyl group contains 8-12 carbon atoms, preferably in an unbranched chain), and on the other hand naphthol-mono- and especially -di-sulphonic acids coupling in o-position to the hydroxy group, and aminonaphtholsulphonic acids (including N-substituted derivatives thereof), preferably coupling in o-position to the amino group.  The products are suitable for dyeing nitrogen-containing fibres, e.g. animal fibres such as leather, silk and especially wool, or artificial fibres of superpolyamides or superpolyurethanes.  Examples describe the preparation of the following dyestuffs: (1) 4-methoxy-3 - aminobenzene - 1 - sulphon - n - dodecylamide-->2 - naphthol - 6 : 8 - disulphonic acid; (2) the same amine-->1-naphthol-3 : 6-disulphonic or -4-sulphonic acid; (3) the same amine, or the corresponding 4-methyl compound -->1 - p - toluenesulphonylamino - 8 - naphthol - 3 : 6 - disulphonic acid; (4) 3 - aminobenzene - 1 - sulphon - n - dodecylamide or its 4 - methyl derivative-->2 - naphthol - 6 : 8-disulphonic acid; (5) 3 - aminobenzene - 1 - sulphon - n - octylamide or n - decylamide--> 2 : 8 : 6 - aminonaphtholsulphonic acid.  In a further example: (6) wool is dyed scarlet with the first product of (2) from a bath containing sodium sulphate and acetic acid.  Lists of additional coupling components are given.  The Specification as open to inspection under Sect. 91 comprises also the use of other coupling components containing a sulphonic acid group, e.g. naphthylamine-mono- and di-sulphonic acids coupling in o-position to the amino group, and 1-phenyl-3-methyl-5-pyrazolones containing sulphonic acid groups. Additional examples describe the preparation of the dyestuffs 4 - methoxy or 6 - methyl - 3 - aminobenzene - 1 - sulphon - n - dodecylamide-->1-(21-chloro-51-sulpho or 21 : 51-disulpho)-phenyl-3 - methyl - 5 - pyrazolone, 3 - aminobenzene-1 - sulphon - n - dodecylamide or its 6-methyl or 6-chloro derivatives-->1-(41-sulpho)-phenyl - 3 - methyl - 5 - pyrazolone, and 3-aminobenzene - 1 - sulphon - n - octylamide--> 2 - naphthylamine - 6 - sulphonic acid or 1-(21 - chloro - 51 - sulpho) - phenyl - 3 - methyl-5 - pyrazolone.  This subject-matter does not appear in the Specification as accepted.