Diastereo- and enantioselective hydrogenation of a challenging enamide derived from 4-phenyl-2-tetralone: an appealing shortcut towards enantiopure cis-2-aminotetraline derivatives

Chem Asian J. 2010 Mar 1;5(3):550-4. doi: 10.1002/asia.200900441.

Abstract

A clean, efficient, and diasteroselective (dr >95%) catalytic hydrogenation of the enamide N-(4-phenyl-3,4-dihydronaphthalen-2-yl)propionamide (2 a) using palladium on carbon is performed. This procedure provides the melatonin receptor ligand (+/-)-cis-4-phenyl-2-propionamidotetralin (cis-4-P-PDOT, 1 a) and its 8-methoxy analog. Furthermore, Rh and Ru catalyzed homogeneous asymmetric hydrogenation of the challenging racemic endocyclic enamide 2 a with several chiral phosphine ligands is studied. The best results, in terms of enantioselectivity, for both diastereomers are obtained when chiral Rh-Josiphos is used as the catalyst.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amides
  • Hydrogenation
  • Ligands
  • Receptors, Melatonin
  • Rhodium
  • Ruthenium
  • Stereoisomerism
  • Tetralones / chemical synthesis
  • Tetralones / chemistry*

Substances

  • Amides
  • Ligands
  • Receptors, Melatonin
  • Tetralones
  • Ruthenium
  • Rhodium