Process for preparing 2-alkylamino- and 2-amino-5-alkylpyridines
US4405790A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 8, 1982 |
| Grant date | Sep 20, 1983 |
| Priority date | — |
| Expiry date | Apr 8, 2002 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D213/74
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
An improved process for preparing the 2-alkylamino-5-alkylpyridine and 2-amino-5-alkylpyridine amination products of 3-alkylpyridines, comprising the step of initially reacting the base directly with the sodium salt of a primary alkylamine to produce the 2-alkylamino form, wherein the alkyl group in each reactant has from 1 to about 20 carbon atoms. The sodium salt is preferably preformed in situ by adding the alkylamine to a dispersion of sodium in an organic solvent heated to about 100.degree.-120.degree. C. The substituted amination preferably proceeds at a temperature of about 100.degree.-140.degree. C. in a solvent such as toluene and under an inert nitrogen atmosphere. The ratio of 2,5-:2,3- isomer products of the reaction is up to about 10:1 or more, with the effective yield of the 2,5-alkylated isomer being about 25% or more. This recovered 2-alkylamino-5-alkylpyridine product is readily dealkylated by reaction with hydrobromic or hydriodic acid with or without the presence of a pyridine hydrohalide salt to obtain the 2-amino-5-alkylpyridine product which has proven uses in herbicidal, insecticidal and pharmaceutical applications.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.