Patent GB-562754-A (GB)
Title: Manufacture of new colouring matters
IPC: C09B23/04
Filed: 1942-07-13
Abstract: Tetra - aryldipyrromonomethines of the formula <FORM:0562754/IV/1> (wherein RI, RII, RIV, and RV stand for aryl radicals, e.g. of the benzene or naphthalene series substituted or not and the same or different, where RIII and RVI each stand for H or for a non-reactive substituent the same or different, e.g. an aryl, alkyl, or acylamino radical, and where R stands for H or an alkyl, aralkyl, or aryl radical or for a heterocyclic residue) are prepared (a) by reacting one or more 2 : 4-diarylpyrroles of the formula <FORM:0562754/IV/2> with a reagent capable of forming a monomethine bridge, or (b) by reacting such a 2 : 4-diarylpyrrole with a carbonyl compound of formula <FORM:0562754/IV/3> Symmetrical or unsymmetrical compounds are obtained.  2 : 4-Diarylpyrroles specified are 2 : 4-diphenylpyrrole, 2-phenyl-4-(p-methoxyphenyl)-pyrrole, 2-(p-methoxyphenyl)-4-phenylpyrrole, 2-(m-hydroxyphenyl)-4-phenylpyrrole, 2-(o-chlorophenyl)-4-phenylpyrrole, 2-(p-acetylaminophenyl)-4-phenylpyrrole, 2-a -naphthyl-4-phenylpyrrole, 2-phenyl-4-b -naphthylpyrrole, 2 : 3 : 4-triphenylpyrrole, 3-benzoylamino-2 : 4-diphenylpyrrole, 3-acetylamino-2 : 4-diphenylpyrrole, 3-benzoylamino-2 : 4-di-p-tolylpyrrole, and 3-acetoacetylamino-2 : 4-diphenylpyrrole. The sulphonic acids of the 2 : 4-diarylpyrroles may be used. Reagents capable of forming a monomethine bridge include ethyl orthoformate, formic acid, chloroform, diphenylformamidine, acetic acid, benzoic acid, benzotrichloride, or 2 : 4-diphenylpyrrole - 5 - carboxylic acid.  Carbonyl compounds specified are 5-formyl-2 : 4-diphenylpyrrole, 5-acetyl-2 : 4-diphenylpyrrole, 5-phenacetyl-2 : 4-diphenylpyrrole, 5-benzoyl-2 : 4-diphenylpyrrole, 2 : 21 : 4 : 41-tetraphenyldipyrrolylketone.  The reaction (a) may be carried out by heating the reagents together in a mutual solvent, e.g. acetic acid, acetic anhydride, or mixtures thereof. Reaction (b) may be similarly effected.  Salts, sulphonic acids, or sulphonates of the compounds may be used for dyeing textiles. Salts with sulphamic acid or quaternary ammonium salts with methyl iodide may be used.  The compounds may be directly sulphonated with fuming sulphuric acid or with chlorosulphonic acid.  In example 1, 2 : 21 : 4 : 41 - tetraphenyldipyrromonomethine is prepared by heating together 2 : 4-diphenylpyrrole, acetic acid, and ethyl orthoformate.  2 : 21 - Diphenyl - 4 : 41 - di - (o - chlorophenyl) - dipyrromonomethine and 2 : 21 - di - (p - meth - oxyphenyl) - 4 : 41 - diphenyldipyrromonomethine are similarly prepared.  In example 2, 2 : 21 : 4-triphenyl - 41 - (p - methoxyphenyl) - dipyrromonomethine is prepared by boiling together 5-formyl-2 : 4-diphenylpyrrole, 2-phenyl-4-(p-methoxyphenyl) - pyrrole, acetic acid, and acetic anhydride.  In example 3, 2 : 21 : 4 : 41-tetraphenylmesophenyldipyrromonomethine is prepared by heating together 2 : 4-diphenylpyrrole, benzotrichloride, and acetic acid. In example 4, 2 : 21 : 4 : 41-tetraphenyl-3 : 31-di-(benzoylamino)-meso - phenyldipyrromonomethine is prepared by heating together 3-benzoylamino-2 : 4-diphenylpyrrole, benzotrichloride, and acetic acid.  In example 5, 2 : 21 : 4 : 41-tetraphenyldipyrrolemonomethine disulphonic acid is prepared by boiling together 2 : 4-diphenylpyrroledisulphonic acid, 5-formyl-2 : 4-diphenylpyrrole, and acetic acid.  In example 6, 2 : 21 : 4 : 41-tetraphenyl-meso-methyldipyrromonomethine is prepared by boiling together 5-acetyl-2 : 4-diphenylpyrrole, 2 : 4-diphenylpyrrole, and phosphorus oxychloride.  2 : 4-Diphenylpyrrole-5-carboxylic acid is prepared by treating 2 : 4-diphenylpyrrole magnesium iodide with CO2. The acid chloride is prepared by reacting the acid with thionyl chloride.  5-Formyl-2 : 4-diphenylpyrrole is prepared by reacting 2 : 4-diphenylpyrrole with formanilide in phosphorus oxychloride. 5-Acetyl-2 : 4-diphenylpyrrole is prepared by reacting 2 : 4-diphenylpyrrole magnesium iodide with acetyl chloride. 5-Phenacetyl- and 5-benzoyl-2 : 4-diphenylpyrrole are similarly prepared.  2 : 21 : 4 : 41-Tetraphenyldipyrrolylketone is prepared by reacting 2 : 4-diphenylpyrrole-5-carboxylic acid chloride and 2 : 4-diphenylpyrrole magnesium iodide.  2 : 4-Diphenylpyrrole magnesium iodide is prepared by reacting 2 : 4-diphenylpyrrole and methyl magnesium iodide.  Specifications 554,102, 556,156 and 562,753 are referred to.  The Provisional Specification also refers to compounds of the general formula in which RIII and RVI stand for benzylideneamino or alkylamino radicals.