METHOD FOR PREPARING PREGABALIN INTERMEDIATE, 3-CARBAMOYMETHYL-5-METHYLHEXANOIC ACID, USING SOLVENT-FREE REACTION

Title:

METHOD FOR PREPARING PREGABALIN INTERMEDIATE, 3-CARBAMOYMETHYL-5-METHYLHEXANOIC ACID, USING SOLVENT-FREE REACTION

Document Type and Number:

WIPO Patent Application WO/2016/155566

Kind Code:

A1

Abstract:

The present invention provides a method for preparing a pregabalin intermediate, 3-carbamoymethyl-5-methylhexanoic acid, using a solvent-free reaction. The method comprises the following steps: a) cooling an ammonia water system to a certain temperature; b) dropwise adding 3-isobutylglutaric anhydride to the system for a temperature holding reaction; c) adding acid to the system for pH regulation after the temperature holding reaction; d) performing cooling after the pH regulation, temperature holding, crystallization, suction filtration and drying; and e) adding a solvent to the dried substance for pulping, and obtaining the final product by means of suction filtration and drying. The method provided in the present invention for preparing 3-carbamoymethyl-5-methylhexanoic acid has high yield, is green, environmentally-friendly, simple and convenient and has low pollution.

Inventors:

LIU MUSONG (CN)
ZHANG WENLING (CN)
WANG PENG (CN)

Application Number:

PCT/CN2016/077338

Publication Date:

October 06, 2016

Filing Date:

March 25, 2016

Export Citation:

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Assignee:

ZHEJIANG HUAHAI PHARM CO LTD (CN)

International Classes:

C07C233/05; C07C231/02

Domestic Patent References:

WO2012093411A2

2012-07-12

Foreign References:

CN101987826A	2011-03-23
CN101448779A	2009-06-03

Other References: