The Most Common Chemical Reactions and Classifications Used in Dye Intermediates

The chemical reactions most commonly used to process raw materials into dye intermediates are as follows

• Sulfonation reactions;

• Nitration reactions;

• Halogenation reactions;

• Reduction reactions for the preparation of amines;

• Diazotization reactions (often accompanied by coupling reactions);

• Substitution of sulfonate groups into hydroxyl groups by alkali fusion reactions;

• Acylation reactions;

• Oxidation reactions;

• Condensation and carbonation reactions;

• Aromatization reactions (mainly amino groups);

• Mutual substitution reactions of hydroxyl and amino groups;

• Hydrocarbonization reactions of hydroxyl or amino groups

According to the structure of the main aromatic ring of fine chemical intermediates, the intermediates can be divided into aliphatic system, benzene system, naphthalene system, anthraquinone system, heterocyclic system and thick ring system. China can produce more than 400 varieties of intermediates of benzene, naphthalene, anthraquinone, heterocyclic and other dye and dye intermediates, which can basically meet the development needs of dye and pigment industry.

Main varieties of benzene system for dye intermediates

2,4-dinitrochlorobenzene, o-nitrochlorobenzene, p-nitrochlorobenzene, p-nitrophenol, N,N-dimethylaniline, p-aminoanisole, p-nitroaniline, o-toluidine, 2-bromo-6-chloro-p-nitroaniline, N-ethylaniline, m-hydroxy-diethylaniline, 2,4-dinitro-6-bromoaniline, o-m-, p-phenylenediamine, 3,3-dichlorobenzidine, bianisidine, p-aminobenzenesulfonic acid o-, p-aminoanisole, DSD acid, p-aminophenetole, CTL acid, o-cyano-p-nitroaniline, acetylacetyl-o-methoxyaniline, p-phenylenediol, m-phenylenediamine, N-methyl-m-toluidine, N-ethyl-m-toluidine, N,N-dimethyl-m-toluidine, N,N-diethyl-m-toluidine, N-methyl-hydroxyethyl-m-toluidine, N-ethyl-hydroxyethyl-m-toluidine, N-methyl-cyanoethyl-m-toluidine, N-ethyl-cyanoethyl-m-toluidine m-toluidine, N-ethyl cyanoethyl m-toluidine, N-methylphenyl m-toluidine, p-toluidine, ethoxyaniline, 2-4-dimethylaniline, 4-chloro-3-aminobenzamide, 4-methyl-3-aminobenzamide, 4-methoxy-3-aminobenzanilide, 4-methoxy-3-amino-N,N-diethylbenzenesulfonamide, 2,4,5-trichloroaniline, m- and para-esters, etc.

Main varieties of naphthalene intermediates of dye intermediates

2-naphthol, H-acid, K-acid, 2,3-acid, 2,6-acid, tartaric acid, 6-methyl-1,2,4 acid oxygenate, J-acid, peri-acid, γ-acid, G-salt, R-salt, amino K-acid, 2-naphthylamine-1,5-disulfonic acid, 1-naphthol-5-sulfonic acid, 1,5-dihydroxynaphthalene, 2,6-naphthalenedicarboxylic acid, 2R-acid, etc. The main varieties of anthraquinone intermediates are: anthraquinone, 1-amino anthraquinone, 1,4-diamino anthraquinone, bromine 1,5-dimethyl anthraquinone, 1,5-diamino anthraquinone, 1-amino-5-benzoyl anthraquinone, 1,5-dihydroxy anthraquinone, 1,8-hydroxy anthraquinone, 1,8-dihydroxy-4,5-diamino anthraquinone, etc.

The main varieties of heterocyclic and thick-ringed dye intermediates

Melamine, barbituric acid, 2-amino-6-nitrobenzothiazole, 2-amino-5,6-dichlorobenzothiazole, 2-amino thiazole, dehydrothio-p-toluidine, bisulfonic acid, 3-hydroxy-4-methyl-6-hydroxy-N-ethylpyridone, 3-formylamino-4-methyl-6-hydroxy-N-ethylpyridone, 4-chloro-1,8-naphthalic anhydride, naphthalenetetracarboxylic anhydride, tetracarboxylic anhydride, etc. .