Preparation of 4-phenyl-1,2,3,6-tetrahydropyridines
US6136981A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 16, 1999 |
| Grant date | Oct 24, 2000 |
| Priority date | — |
| Expiry date | Jun 16, 2019 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D211/70
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process for the preparation of a compound of the formula ##STR1## wherein R.sub.1 is selected from the group consisting of hydrogen and alkyl of 1 to 8 carbon atoms, R.sub.2 and R.sub.4 are alkyl of 1 to 4 carbon atoms and R.sub.3 is alkyl of 1 to 8 carbon atoms comprising reacting a compound of the formula ##STR2## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are defined as above or an amine salt thereof with an electrophilic halogenating agent to obtain a compound of the formula ##STR3## wherein Hal.sub.1 is halogen, reacting the latter with a halohydroxylating agent to obtain a compound of the formula ##STR4## wherein Hal.sub.2 is halogen, reacting the latter with a base to obtain a compound of the formula ##STR5## reacting the latter with a diastereoselective reducing agent to obtain a compound of the formula ##STR6## reacting the latter with a reducing agent to obtain a cis racemic compound of formula I and optionally resolving the latter with a resolution agent to obtain the desired optical form and novel intermediates.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.