Patent GB-276126-A (GB)
Title: Process for manufacturing products of conversion of peri-cyannaphthalene sulphonic acids
IPC: C07C51/367
Filed: 1926-07-28
Abstract: 276,126. Carpmael, W., (I. G. Farbenindustrie Akt.-Ges.). July 28, 1926. Naphthalene derivatives; azo dyes.-8-Cyanonaphthalene-1-sulphonic acid, its derivatives substituted in the sulphonic group, and its nuclear substitution products (obtainable from 8-aminonaphthalene-1-sulphonic acid and its nuclear substitution products by diazotizing and treating with cuprous cyanide, according to Sandmeyer's reaction.) are treated (a) with acid saponifying agents to yield 1-sulphonaphthalene-8-carboxylic acid, its inner anhydride and their nuclear substitution products, which may be converted into 1 : 8-oxynaphthoic acid and its nuclear substitution products by treating with alkalies, or (b) with alkaline acting agents to yield 1 : 8-aminonaphthoic acid, naphthostyril, and their nuclear substitution products. 8-Naphthamide-1-sulphonic acid and its nuclear substitution products are formed intermediately and may be isolated. In examples (1) 8-cyanonaphthalene-1-sulphonic acid (sodium salt) is heated with concentrated sulphuric acid; the inner anhydride of 1-sulphonaphthalene-8-carboxylic acid is obtained and may be converted into the acid by warming with water, or the acid mav be obtained directly by warming the 8-cyanonaphthalene-1-sulphonic acid with dilute mineral acids; (2) 1 : 8-oxynaphthoic acid is obtained by heating the inner anhydride or an alkaline salt of 1-sulphonaphthalene-8-carboxylic acid with potash in the presence of water or methyl alcohol, or by heating the anhydride with caustic soda lye in an autoclave. the product being diluted with water and acidified: (3) naphthostyril is obtained by heating 8- cyanonaphalene-1-sulphonic acid with potash in the presence of water or methyl alcohol; it may be saponified to 1-aminonaphthalene-8-carboxylic acid by boiling the fused mass with water, nr the acid may be obtained directly by boiling 8- cyanonaphthalene-1-sulphonic acid with caustic soda lye; by interrupting the reaction before its completion, and diluting with water, the difficultly-soluble sodium or potassium salt of 8- naphthamide-1-sulphonic acid is obtained: this may be converted into naphthostyril by treating with alkaline agents, e.g. caustic alkalies, sodium formate or sodium acetate, or into 1-sulphonaphthalene-8-carboxylic acid by treating with dilute acids: (4) 4-chlornaphthostyril, which can be saponified to 4-chlor-1-aminonanhthalene-8-carboxylic acid-the latter body is diazotizable and capable of combining with diazo compounds-is obtained by treating 8-cyano-4-chlornaphthalene- 1-sulphonic acid (from 8-amino-4-chlornaphthalene-1-sulphonic acid by Sandmeyer's reaction) with potash; (5) 5-oxynaphthostyril, which will couple with diazo compounds, is obtained by treating 8-cyanonaphthalene-1 : 5-disulphonic acid (from 8-aminonaphthalene-1 : 5-disulphonic acid by Sandmeyer's reaction) with potash; it can be alkylated in the hydroxy group by treating with esters of p-toluenesulphonic acid; the methoxy and ethoxy derivatives are described; they can be saponified to the corresponding 5-alkoxy-1- aminonaphthalene-8-carboxylic acids, which can be diazotized and coupled with oxy or amino compounds to yield azo dyestuffs, or coupled with diazo compounds; (6) 8-cyanonaphthalene-1 : 5-disulphonic acid is heated with potash and methyl alcohol ; according to the conditions, 5-oxy-8- naphthamide-1-sulphonic acid (which will couple with diazo compounds) or 5-oxynaphthostyril are obtained; (7) 8-cyanonaphthalene-1 : 3 (or 1 : 6)- disulphonic acid (from 8-aminonaphthalene-I : 3 (or 1: 6)-disulphonic acid by Sandmeyer's reaction) when treated with potash and methyl alcohol yields, according to the conditions, 3- or 6-sulphonaphthostyril, 3- or 6-sulpho-1-aminonaphthalene-8-carboxylic acid (which is diazotizable and will couple with diazo compounds), 3- or 6-oxynaphthostyril and 3- or 6-oxy-1-aminonaphthalene-8-carboxylic acid (these compounds will couple with diazo compounds and the free acid can 'also be diazotized); the oxy compounds may be alkylated by treating with alkylating agents; and (8) salts of 8-cyanonaphthalene-1-sulphonic acid and 1 : 6-disulphonic acid are heated with milk of lime in an autoclave: the products are 1-aminonaphthalene-8-carboxylic acid and 6-sulpho-l-aminonaphthalene-8-carboxylic acid respectively.