- Synthesis method of 8-amino-2-naphthol
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The invention relates to a synthesis method of 8-amino-2-naphthol, and belongs to the technical field of fine chemical intermediates. The method comprises the following steps: taking 2-naphthaleneboronic acid as a raw material, nitrating with acetic acid and concentrated nitric acid to obtain 8-nitro-2-naphthaleneboronic acid, reducing with iron powder or palladium on carbon, and oxidizing with hydrogen peroxide to obtain 8-amino-2-naphthol. According to the synthesis method, the problem of selectivity during nitration reaction is solved, boric acid groups are smoothly converted into hydroxyl groups again through oxidation, process conditions are relatively mild, and a high-purity product can be obtained only through recrystallization in the final reaction step.
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Paragraph 0008; 0035-0036
(2022/02/24)
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- Method for preparing 8-acetamido-2-naphthol
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The invention provides a method for preparing 8-acetamido-2-naphthol and belongs to the technical field of compound preparation methods. The preparation method comprises the following steps: 8-amino-2-naphthalene sulfonic acid and alkali metal hydroxides according to a molar ratio of 1:(3-12), mixing with an organic solvent in an autoclave, and performing alkali fusion at the temperature of 160-320 DEG C and the pressure of 0-1.5MPa so as to prepare 8-amino-2-naphthol; and recovering the organic solvent from the prepared reactants, carrying out an amidation reaction on the prepared 8-amino-2-naphthol and acetic acid or acetic anhydride at the reaction temperature of 20-40 DEG C so as to obtain 8-acetamido-2-naphthol, performing suction filtration, pressing to dry, thereby obtaining the 8-acetamido-2-naphthol. The preparation method is simple in process, less by-products are produced in the reaction, the sulfonate purity is high, the high-purity 8-acetamido-2-naphthol can be directly prepared by alkali fusion without refining, the production cost is reduced, lots of acidic wastewater is not produced, and the environmental protection is facilitated.
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Paragraph 0021; 0022; 0023; 0024
(2018/04/27)
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- Method for preparing adduct of butadiene polymer or copolymer and α, β-ethylenically unsaturated dicarboxylic acid compound
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In a method for preparing an adduct of (A) a butadiene lower polymer or butadiene lower copolymer and (B) a α,β-ethylenically unsaturated dicarboxylic acid compound, said method is characterized in that said (A) and (B) are caused to react in the presence of one or more compounds selected from (C) p-phenylenediamine derivatives, catechol derivatives, pyrogallol derivatives, N-nitrosamines, quinoline derivatives and naphthol derivatives, thus serious increase of the viscosity of said adduct in the addition reaction can be prevented.
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