Process for the production of 1,4,5,6-tetrahydropyrazine-2-carboxylic acid amides
US5939549A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 11, 1997 |
| Grant date | Aug 17, 1999 |
| Priority date | — |
| Expiry date | Jul 11, 2017 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D241/06
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process for the production of 1,4,5,6-tetrahydropyrazine-2-carboxylic acid amides of the general formula (I), where R.sup.1 means hydrogen, alkyl, cycloalkyl or arylalkyl, R.sup.2 means alkyl, aryl or arylalkyl and R.sup.3, R.sup.4 and R.sup.5 mean independently from each other hydrogen, alkyl, aryl or arylalkyl or R.sup.2 forms an alicyclic system with R.sup.3 or R.sup.4 and the adjacent C atom(s), R.sup.6 being hydrogen or acyl. The products are obtained from the corresponding tetrahydropyrazine carboxylic acid nitriles and olefins or corresponding carbenium ion precursors and possibly carboxylic acids in a Ritter reaction. The products are new and can be used, for example, for the production of piperazine carboxylic acid amides. ##STR1##
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.