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Preparation method of p-hydrazine benzene sulfonamide hydrochloride

A technology of hydrazine benzene sulfonamide and chlorobenzene sulfonamide is applied in the field of preparation of p-hydrazine benzene sulfonamide hydrochloride, which can solve the problems of high equipment requirements, easy decomposition of diazonium salts, and many by-products, etc. The effect of low requirements, high reaction yield, and high product purity

Active Publication Date: 2019-09-20
CHANGZHOU YONGHE FINE CHEM
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  • Description
  • Claims
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Problems solved by technology

[0005] (1) The diazonium salt is easy to decompose, resulting in more by-products, affecting the reaction yield and product purity
[0006] (2) In order to improve the reaction yield and product purity, Document 2 uses a special catalyst, while Document 3 uses a special reaction device, the former obviously leads to production costs increase, the latter obviously has higher requirements on equipment and is not suitable for large-scale industrial production

Method used

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Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1）

[0016] The preparation method of the hydrazinobenzenesulfonamide hydrochloride of the present embodiment is as follows:

[0017] Add 19.2kg of p-chlorobenzenesulfonamide (0.1kmol) and 62.5kg of hydrazine hydrate (1.0kmol) with a mass percentage of 80wt% into the autoclave. After nitrogen replacement, heat up to 121±1°C, and then blow nitrogen to The pressure is 1.0MPa, and the reaction is carried out under heat preservation and pressure, and the reaction is terminated when the content of p-chlorobenzenesulfonamide is ≤0.1% by sampling.

[0018] After the reaction, cooling and crystallization, suction filtration, and acidification of the filter cake with hydrochloric acid, 21.8 kg of p-hydrazinobenzenesulfonamide hydrochloride was obtained with a yield of 97.5% and an HPLC purity of 98.7%.

Embodiment 2～ Embodiment 3）

[0020] The preparation method of each embodiment is basically the same as that of Example 1, and the differences are shown in Table 1.

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Abstract

The invention discloses a preparation method of p-hydrazine benzene sulfonamide hydrochloride. P-chlorobenzenesulfonamide and hydrazine hydrate react at the temperature of 120-125 DEG C under the pressure of 0.8-1.2MPa to prepare the p-hydrazine benzene sulfonamide hydrochloride. The mole ratio of the p-chlorobenzenesulfonamide to the hydrazine hydrate is 1:8-1:15, and the mass percent of the hydrazine hydrate is 50wt%-80wt%. According to the method, the p-hydrazine benzene sulfonamide hydrochloride is prepared from the p-chlorobenzenesulfonamide and the hydrazine hydrate with about 10 times of mole equivalent under the conditions of high temperature and high pressure, high reaction yield and high product purity can be acquired, production cost is low, requirements for devices are low, and the method is suitable for industrial mass production.

Description

technical field [0001] The invention belongs to the technical field of preparation of pharmaceutical intermediates, and in particular relates to a preparation method of p-hydrazinobenzenesulfonamide hydrochloride. Background technique [0002] P-hydrazinobenzenesulfonamide hydrochloride [also known as 4-sulfonamidophenylhydrazine hydrochloride, referred to as PHSF.HCl, CAS No. 17852-52-7] is an important pesticide, pharmaceutical and dye intermediate. It is mainly used in the production of celecoxib. [0003] At present, the main method for preparing p-hydrazinobenzenesulfonamide hydrochloride is still to use p-aminobenzenesulfonamide as raw material, and prepare it through diazotization, reduction, salt formation and other reactions [see Documents 1 to 3]. [0004] This method mainly has the following deficiencies: [0005] (1) The diazonium salt is easy to decompose, resulting in more by-products, which affects the reaction yield and product purity. [0006] (2) In orde...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): C07C303/40C07C311/39
CPCC07C303/40C07C311/39
Inventor 宋菊红陆海峰姜友林许晓春陈云峰
Owner CHANGZHOU YONGHE FINE CHEM
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