Title:
PROCESS FOR CONTINUOUS FLOW SYNTHESIS OF 4-CHLOROPHENYLHYDRAZINE SALT
Document Type and Number:
WIPO Patent Application WO/2018/019249
Kind Code:
A1
Abstract:
The present invention provides a process for continuous flow synthesis of a 4-chlorophenylhydrazine salt; the three reaction steps of diazotization, reduction, and acidolysis salt formation are organically integrated in an innovative manner; using a 4-chloroaniline acidic stock solution, a diazotization reagent, a reducing agent, and acid as starting materials, continuously performing in sequence the three reaction steps of diazotization, reduction, and acidolysis salt formation to obtain a 4-chlorophenylhydrazine salt; the synthesis process is carried out in an integrated reactor and is an integrated solution. The reaction starting materials are added continuously via the material feed inlet of the integrated reactor; the three reaction steps of diazotization, reduction, and acidolysis salt formation are performed continuously in sequence in the integrated reactor; 4-chlorophenylhydrazine salt is obtained continuously from the material outlet of the integrated reactor; the total reaction time is ≤20 minutes. In comparison with conventional production processes, the total reaction time is greatly shortened and safety is significantly improved; furthermore, neither the reaction process nor the reaction product contain any reaction by-products (such as diazoamino compounds and reduction reaction intermediates); the described continuous flow process does not require an additional purification step and produces a high-purity product having a purity of 99% or higher, while also achieving a maximum yield of 99.5% or higher.
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Inventors:
MA BING (CN)
PAN SHUAI (CN)
PU DENGPAN (CN)
PAN SHUAI (CN)
PU DENGPAN (CN)
Application Number:
PCT/CN2017/094435
Publication Date:
February 01, 2018
Filing Date:
July 26, 2017
Export Citation:
Assignee:
SHANGHAI HYBRID-CHEM TECH (CN)
International Classes:
C07C241/02; B01J19/00; C07C243/22
Foreign References:
| CN102993044A | 2013-03-27 |
Other References:
ZHIQUN YU: "Continuous-Flow Process for the Synthesis of 2-Ethylphenylhyd- razine Hydrochloride", PROCESS RES. DEV., no. 19, 12 June 2015 (2015-06-12), pages 892 - 896, XP055602770
ZHIQUN YU: "Continuous-Flow Process for the Synthesis of 2-Ethylphen-ylhydrazine Hydrochloride", PROCESS RES. DEV., 12 June 2015 (2015-06-12), XP055602770
ZHIQUN YU: "Continuous-Flow Process for the Synthesis of 2-Ethylphen-ylhydrazine Hydrochloride", PROCESS RES. DEV., 12 June 2015 (2015-06-12), XP055602770
Attorney, Agent or Firm:
ZHEJIANG HANGZHOU JINTONG PATENT OFFICE CO.,LTD (CN)
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