Method for preparing pregabalin intermediate 3-carbamoymethyl-5-methylhexanoic acid without solvent
US10173965B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 25, 2016 |
| Grant date | Jan 8, 2019 |
| Priority date | — |
| Expiry date | Mar 25, 2036 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C231/24
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The present invention provides a method for preparing a pregabalin intermediate 3-carbamoymethyl-5-methylhexanoic acid without solvent. The method comprises the following steps: a) cooling an ammonia water system to a certain temperature; b) adding 3-isobutylglutaric anhydride dropwise to the system, then keeping temperature, and reacting; c) after completing the reaction, adding an acid to the system to adjust pH; d) after adjusting pH, cooling, then keeping temperature, crystallizing, then suction filtering and drying; and e) adding a solvent to the dried substance, slurrying, and suction filtering and drying to obtain the final product. The method provided in the present invention for preparing 3-carbamoymethyl-5-methylhexanoic acid is high-yield, green, environmentally-friendly, simple and convenient, and of less pollution.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.