Patent · US Expired

Process for recycling amine isomer

US5082970A · kind A · utility

19Cited by
4References
23Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 6, 1991
Grant dateJan 21, 1992
Priority date
Expiry dateMar 6, 2011

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P20/582
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

A novel process for converting trans-isomeric N-methyl-4-(3,4-dichlorophenyl)-1,2,3,4-tetrahydro-1-naphthaleneamine to cis-isomeric N-methyl-4-(3,4-dichlorophenyl)-1,2,3,4-tetrahydro-1-naphthaleneamine is disclosed. The process involves contacting trans-isomeric N-methyl-4-(3,4-dichlorophenyl)-1,2,3,4-tetrahydro-1-naphthaleneamine, or a mixture of same with up to about an equal part by weight of the corresponding cis-isomer, with a basic equilibration agent like potassium tert.-butoxide in a reaction-inert polar organic solvent to ultimately afford a cis/trans-mixture wherein the amount of cis-amine present in said mixture achieves a constant value of about 2:1 on a weight-by-weight basis. The aforesaid resultant mixture is useful as an intermediate product that ultimately leads to pure cis-(1S) (4S)-N-methyl-4-(3,4-dichlorophenyl)-1,2,3,4-tetrahydro-1-naphthaleneamine (sertraline), which is a known antidepressant agent.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.