A kind of method for preparing 4,6-diaminoresorcinol hydrochloride by resorcinol one-pot method

Abstract

The invention discloses a method for preparing 4,6-diamino resorcinol hydrochloride by a resorcinol one-pot method. The method comprises the following steps of (1) uniformly mixing and dissolving methanesulfonic acid, an acylation reagent and resorcinol according to a mole ratio of (2 to 8) to (2 to 5) to 1; performing reaction for 1 to 3h at 80 to 140 DEG C, wherein the acylation reagent is acetic acid or acetic anhydride; (2) after the reaction in the step (1) is completed, adding hydroxylamine with the mole ratio of the acylation reagent to the hydroxylamine being (1 to 2) to 1; continuously performing reaction for 2 to 5h; (3) after the reaction in the step (2) is completed, performing amide hydrolysis and hydrochlorination reaction; performing cooling and crystallization on products to obtain the 4,6-diamino resorcinol hydrochloride. Through the reaction steps of acylation, oximation, rearrangement, hydrolysis, hydrochlorination and the like, the 4,6-diamino resorcinol hydrochloride is prepared by the one-pot method through the proper communicated reagent; a large number of purification processes in the middle process are avoided; the reaction steps are simplified; the occurrence of side reactions is reduced; the production efficiency is greatly improved; the cost is reduced.

Description

technical field [0001] The invention belongs to the field of organic synthesis, and in particular relates to a method for preparing 4,6-diaminoresorcinol hydrochloride by a one-pot method of resorcinol. Background technique [0002] Poly-p-phenylene-benzobisoxazole fiber (Poly-p-phenylene-benzobisoxazole, referred to as PBO), known as the 21st century super fiber. The high temperature resistance of PBO fiber is the highest among organic materials; its tensile strength and modulus are much higher than those of carbon fibers, and it is the fiber material with the largest tensile strength and modulus so far; at the same time, its flame resistance is also The best among organic materials; it also has the characteristics of corrosion resistance, low density, etc. Due to this excellent performance characteristic, it has important applications in key and special fields such as national defense and military industry, aerospace, fire prevention and fire protection. However, at pres...

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Problems solved by technology

[0006] Aiming at the above-mentioned deficiencies in the prior art, the present invention investigates the similarities between the resorcinol acylation reaction and oximation, rearrangement and other reactions through a series of experiments, and designs and develops a suitable one that can be used as both acylation reaction and As the same catalyst and solvent for oximation and Beckmann rearrangement reactions, the purpose is to directly prepare the target product of 4,6-diaminoresorcinol hydrochloride from resorcinol in one step, and solve the problem of existing preparation of 4,6 -The problem of numerous steps in the method of diaminoresorcinol hydrochloride, while fundamentally solving the problem of difficult preparation of 4,6-diaminoresorcinol hydrochloride

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