A preparation method of original dye of Vat Brown R comprises the following steps: a. after acylation of 1,5-diaminoanthraquinone, 1-amino-5-benzamidoanthraquinone was prepared by acidic hydrolysis; b. 1-benzamido-4-bromoanthraquinone was obtained from 1-aminoanthraquinone by acylation and bromination; c. a condensate of Vat Brown R was obtained by condensation reaction of 1-amino-5-benzamidoanthraquinone and 1-benzamido-4-bromoanthraquinone; d. the original dye of Vat Brown R was obtained from the condensate of Vat Brown R by ring closing reaction and oxidation reaction. The method omits one oxidation step, economizes significant amount of oxidizing agent, and reduces significant amount of waste water, so it is very beneficial to environment protection; and the method also exhibited the advantages of highly increasing product yield and reducing the costs of raw materials to an extent of more than 30%.
Vat Brown R的原料
染料制备方法包括以下步骤:a.在1,5-二
氨基
蒽醌酰化后,通过酸性
水解制备1-
氨基-5-苯甲酰基
蒽醌; b.从1-
氨基
蒽醌酰化和
溴化中获得1-苯甲酰基-4-
溴蒽醌; c.通过1-
氨基-5-苯甲酰基
蒽醌和1-苯甲酰基-4-
溴蒽醌的缩合反应获得Vat Brown R的缩合物; d.通过环合反应和氧化反应从Vat Brown R的缩合物中获得原料
染料。该方法省略了一个氧化步骤,节约了大量氧化剂,并减少了大量废
水,因此对环境保护非常有益;此外,该方法还表现出高增加产品产量和降低原材料成本的优点,降低了30%以上的成本。