Patent GB-806817-A (GB)
Title: Heterocyclic polymethine dyes
Inventor: BERRIE ALISTAIR HOWARD
IPC: C09B23/16
Filed: 1956-07-27
Abstract: Diaryl, diindolinyl and diquinolinyl alkanes of the general formula <FORM:0806817/IV (b)/1> where R and R1 are the same or different and are hydrogen or alkyl or may be joined together to form with the carbon atom a cycloalkyl ring which may contain alkyl substituents, R2 is alkyl or alkylene which is connected to the ring A in a position ortho to the nitrogen atom to form a heterocyclic ring, and rings A may be substituted, are made by reacting a cycloalkanone or an aliphatic aldehyde or ketone and at least 2 molecular proportions of an N-alkyl derivative of an aniline, or an indoline or a tetrahydroquinoline at elevated temperature in a medium containing at least one equivalent of acid for each molecular proportion of amine. Hydrochloric acid may be used.  Aldehydes and ketones specified are cyclopentanone, cyclohexanone, 3-methylcyclohexanone, formaldehyde, acetaldehyde, n-butyraldehyde, acetone, methyl ethyl ketone and methyl n-butyl ketone.  Amines mentioned are N-ethylaniline, N-methyl-o-toluidine, N-n-butylaniline, indoline, 2-methyl indoline and 8-chloro-tetrahydroquinoline.  Examples describe the preparation of: (I) bis-(2-methyl-5-indolinyl-) methane; and (II) 2 : 2-bis-(1 : 2 : 3 : 4-tetrahydro-6-quinolyl)-propane.  Bis - (1 : 2 : 3 : 4 - tetrahydro - 6 - quinolyl-) - methane disulphonic acid is made by sulphonating bis - (1 : 2 : 3 : 4 - tetrahydro - 6 - quinolyl-)-methane with 20 per cent oleum.  2 - Aldehydo - methylene - 1 : 3 : 3 - trimethyl indolines containing an n-butyl group or a chlorine atom in the 5-position, and 2-aldehydo - methylene - 1 - n - butyl - 3 : 3 - dimethyl indoline are made by reacting 5-butyl- or 5-chloro - 2 - methylene - 1 : 3 : 3 - trimethyl indoline or 1-n-butyl-3 : 3-dimethyl-2-methylene indoline with N : N - formyl - methyl aniline and phosphorus oxychloride by the method of Specification 438,278 for the preparation of 2-aldehydo-methylene-1 : 3 : 3-trimethyl indoline.  2 - Aldehydo - methylene - 1 : 3 : 3 - trimethyl indoline sulphonic acid is made by sulphonating 2 - aldehydo - methylene - 1 : 3 : 3 - trimethyl indoline with oleum.  5 - Butyl - and 5 - chloro - 2 - methylene - 1 : 3 : - trimethyl indolines are made by the method of Plancher, Chemiker-Zeitung 1898, page 38, for making 2-methylene-1 : 3 : 3-trimethyl indoline by replacing the phenyl hydrazine by equivalent amounts of 4-n-butyl-and 4-chloro-phenyl hydrazines respectively.ALSO:The invention comprises greenish-yellow wool dyes of the formula (I) <FORM:0806817/IV (c)/1> or the alkali-metal salts thereof wherein R and R1 may be the same or different and are hydrogen or alkyl or may be joined together to form with the carbon atom a cycloalkyl ring which may contain alkyl substituents, R2 is alkyl or alkylene which is connected to ring A in a position ortho to the nitrogen to form a heterocyclic ring, R3, T4 and R5 are alkyl and may be the same or different, and rings A and B may be further substituted.  The invention further comprises processes for preparing the dyes by sulphonating a compound of the formula (II) <FORM:0806817/IV (c)/2> where X is an anion, such as hydroxy, chloride or sulphate, or by reacting together in acid medium one molecular proportion of a compound of the formula (III) <FORM:0806817/IV (c)/3> and at least two molecular proportions of a compound of the formula (IV) <FORM:0806817/IV (c)/4> provided that each of rings A and B contains not more than one sulphonic acid group, and sulphonating any compound so obtained which contains less than four sulphonic acid groups.  The interaction and sulphonation may be carried out in a single operation.  The sulphonation may be effected by stirring the compound in oleum at between 0 DEG  and 100 DEG  C. until a test portion is readily soluble in 50 to 100 parts of cold water.  Alkyl groups specified as R and R1 are methyl, ethyl and n-butyl, and cycloalkyl rings formed when R and R1 are joined may be cyclopentane, cyclohexane and methyl cyclohexane.  R3, R4 and R5 may be methyl, n-butyl and n-octyl, and R2 may be methyl, ethyl and n-butyl and, when alkylene, may be ethylene, trimethylene and propylene.  Substituents present in rings A and B may be methyl, n-butyl, n-octyl, methoxy, carbethoxy, acetamido, propionamido, chlorine and bromine. Compounds of the above general formula II are made by reacting one molecular proportion of the compound of formula (III) with 2 molecular proportions of the compound of formula (IV), both rings A and B being unsulphonated, at elevated temperatures in an acidic medium such as aqueous hydrochloric or sulphuric acid, glacial acetic acid either alone or containing small amounts of hydrochloric or sulphuric acid, or solutions of phosphorus oxychloride in benzene or monochlorobenzene.  Examples are given. Specification 438,278, [Group IV], is referred to.