Preparation method for 1-substituted-1H-1,2,3-triazole 4-carboxylic acid
US10487063B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 16, 2015 |
| Grant date | Nov 26, 2019 |
| Priority date | — |
| Expiry date | Nov 22, 2035 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D249/04
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Provided is a preparation method for 1-substituted-1H-1, 2, 3-triazole-4-carboxylic acid. 1-Substituted-4, 5-dibromo-1H-1,2,3-triazole is added to an isopropylmagnesium chloride to obtain 1-substituted-4-bromo-1H-1,2,3-triazole by a reaction; then an isopropylmagnesium chloride-lithium chloride composite is added directly to obtain a mixture of 1-substituted-1H-1,2,3-triazole-4-carboxylic acid and 1-substituted-4-bromo-1H-1,2,3-triazole-5-carboxylic acid; secondly, to the mixture, a base and iodomethane are added to obtain 1-substituted-4-bromo-1H-1,2,3-triazole-5-carboxylic acid methyl ester by a reaction; the aqueous layer is adjusted with hydrochloric acid to pH=1-5, extracted with an organic solvent and dried; then 1-substituted-1H-1,2,3-triazole-4-carboxylic acid is obtained by concentration and crystallization. The method is suitable for industrialized production and has a greater application value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.