Process for preparing isopimaric acid
US8946469B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 4, 2010 |
| Grant date | Feb 3, 2015 |
| Priority date | — |
| Expiry date | Apr 25, 2031 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C2603/22
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Disclosed is a process for preparing isopimaric acid, comprising the following steps: First step: dissolving thermally isomerized rosin in acetone, adding in drops a solution of isobutanolamine in acetone to form a precipitate, standing, filtering, washing with ethanol, and drying to obtain crude ammonium salt of isopimaric acid; recrystallizing the crude ammonium salt of isopimaric acid according to multi-recrystallization, and drying to obtain purified crystal of ammonium salt of isopimaric acid; Second step: dissolving the purified crystal of ammonium salt of isopimaric acid obtained in the first step in ether, adding hydrochloric acid in portions until the crystal of ammonium salt of isopimaric acid disappears, removing a water layer and washing the ether layer with water to neutral, evaporating the ether, dissolving the residue in acetone, adding water slowly into the solution dropwise until crystals cease to grow, then filtering and drying to obtain purified isopimaric acid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.