Methods for preparing eutectic mixtures of p-hydroxybenzoic acid esters
US4309564A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 23, 1980 |
| Grant date | Jan 5, 1982 |
| Priority date | — |
| Expiry date | Oct 23, 2000 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C69/88
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Novel methods of forming in situ eutectic mixtures of three or more lower alkyl esters of p-hydroxybenzoic acid are disclosed which avoid the prior art methods of forming the respective esters independently and blending them, for example, by melting. Such eutectic mixtures may be formed in situ by first reacting a p-hydroxybenzoic acid and a lower alkanol in the presence of an esterification catalyst to form a first lower alkyl ester of p-hydroxybenzoic acid, reacting the resulting mixture with two or more lower alkanols under heat to form a mixture of three or more lower alkyl esters of p-hydroxybenzoic acid, quenching the reaction when the ratio of the respective lower alkyl esters of p-hydroxybenzoic acid to each other is such that the mixture thereof is liquid at room temperature and isolating the resulting eutectic mixture. Other methods of preparing such eutectic mixtures in situ are also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.