Process for the selective hydroxymethylation of nitrotoluenes
US4299992A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | May 20, 1980 |
| Grant date | Nov 10, 1981 |
| Priority date | — |
| Expiry date | May 20, 2000 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C201/12
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The invention relates to a new process for the selective hydroxymethylation of substituted ortho- or paranitrotoluenes of the general formula (I) ##STR1## in order to prepare nitrophenylalkanols of the general formula (II) ##STR2## In the above formulae the nitro group is attached to the benzene ring in ortho or para position related to the methyl group or the hydroxyalkyl side chain, respectively, X stands for hydrogen, fluorine or an alkyl, alkoxy or nitro group, and n is 1, 2 or 3. According to the process of the invention the starting substance is hydroxymethylated with an excess of formaldehyde at a temperature above room temperature in dimethyl formamide and in the presence of a strong base. The reaction is performed in dimethyl formamide containing 0.1 to 1% by weight of water, and the reaction is directed to the formation of the required end-product by properly adjusting the temperature and the amount of formaldehyde and the base with respect to the starting compound of the general formula (I). In this way the required end-products can be prepared selectively also on an industrial scale.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.