Lanthanide Intermediate

- Mar 26, 2019-

  The intermediate of anthraquinone series is a class of dye intermediates. It is an anthracene derivative containing anthracene and a substituent containing a nitro group, a sulfonic acid group, a halogen group, an amino group, a hydroxyl group, a methyl group and a carboxyl group, and is mainly used for producing an anthraquinone dye.

   Intermediates prepared from hydrazine: mainly used in the preparation of vat dyes, acid dyes, disperse dyes, reactive dyes and direct dyes. Such intermediates can be prepared by a series of organic synthesis unit processes such as nitration, sulfonation, halogenation, reduction, and amination. It can be obtained by oxidation of strontium, but this method is limited by the source of cockroaches. In addition, hydrazine can also be obtained by condensing phthalic anhydride with benzene in the presence of aluminum trichloride and then cyclizing it in concentrated sulfuric acid. As the demand for antimony grows, new synthetic routes are being developed, such as the naphthoquinone process and the styrene process. The hydrazine is reduced with zinc powder in concentrated sulfuric acid, and then condensed with acrolein to obtain a benzene fluorenone (1). The hydrazine is nitrated to give 1-nitroindole (2), which contains the impurities 2-nitroguanidine and various dinitroguanidines, which must be purified by sodium sulfite to prepare other lanthanide intermediates.

   Recently, a new route for the synthesis of 1-nitroguanidine has been developed, which is obtained by cyclization and dehydrogenation using 5-nitro-1,4-naphthoquinone and butadiene as raw materials. Reduction of 1-nitroguanidine gives 1-aminoindole (3) which is then sulfonated and brominated to form 1-amino-4-bromoindole-2-sulfonic acid (bromo) (4). 1-Aminoguanidine dibromination gives 1-amino-2,4-dibromoindole (5), which is then hydrolyzed in sulfuric acid to give 1-amino-2-bromo-4-hydroxyindole (6). 1-nitroguanidine and sodium sulfite are first reacted with hydrazine-1-sulfonic acid, and then chlorinated to form 1-chloroindole (7). After nitrification and separation, 1,5-dinitroguanidine (8) can be obtained, and then 1,5-diaminopurine (9) is obtained by reduction reaction, and ruthenium-2-sulfonic acid is obtained from ruthenium. It is obtained by sulfonation with fuming sulfuric acid, which has been used in the past to produce 2-aminoindole (10). The oxime-2-sulfonic acid is sulfonated with a relatively concentrated fuming sulfuric acid to obtain 2,6-nonanedisulfonic acid (11) and 2,7-anthracene disulfonic acid. The amination of 2,6-nonanedisulfonic acid gives 2,6-diaminopurine (12).Sulfonation with fuming sulfuric acid in the presence of a mercury locating agent, depending on the sulfonation depth, anthraquinone-1-sulfonic acid (13), 1,5-anthracene disulfonic acid (14) And 1,8-anthracene disulfonic acid (15).anthraquinone-1-sulfonic acid is nitrated, chlorinated and reduced to give 1-chloro-5-aminoindole (16); it can also be obtained by amination or chlorination to obtain 1-aminoindole (3), 1-chloroanthraquinone (7). 1,5-nonanedisulfonic acid and 1,8-anthracene disulfonic acid can be prepared into 1,4,5,8-tetrachloroindole (17) by sulfonation, chlorination or the like. 1,5-decanedisulfonic acid and 1,8-decanedisulfonic acid can be obtained by pressurizing alkali fusion to obtain 1,5-dihydroxyindole (18) and 1,8-dihydroxyindole (19), respectively. 1,5-dihydroxyindole, 1,8-dihydroxyindole may also be obtained by diazotization and hydrolysis of the corresponding 1,5-diaminopurine, 1,8-diaminopurine; or may also be 1 5-Nitroindole and 1,8-nitroindole are hydrolyzed in sulfolane with calcium hydroxide at a high temperature and then acidified.

   The lanthanide intermediates prepared from phthalic anhydride are suitable for those lanthanide derivatives which cannot be directly prepared from hydrazine. Condensation of phthalic anhydride with chlorobenzene, ring synthesis of 2-chloroindole (20), followed by amination to form 2-aminoindole (10). Phthalate anhydride is condensed with hydroquinone or p-chlorophenol to form 1,4-dihydroxyindole (21), which is then aminated to form 1,4-diaminopurine (22). Phthalic anhydride is condensed with toluene and cyclized to give 2-methylindole (23). 2-Methyl hydrazine is chlorinated and oxidized to give 1-chloroindole-2-carboxylic acid (24). 2-Aminopurine-2-carboxylic acid (25) can be obtained by nitration, oxidation and reduction of 2-methylhydrazine.