Molecules (Dec 2015)

Efficient Synthesis of β-Aryl-γ-lactams and Their Resolution with (S)-Naproxen: Preparation of (R)- and (S)-Baclofen

  • Iris J. Montoya-Balbás,
  • Berenice Valentín-Guevara,
  • Estefanía López-Mendoza,
  • Irma Linzaga-Elizalde,
  • Mario Ordoñez,
  • Perla Román-Bravo

DOI
https://doi.org/10.3390/molecules201219830
Journal volume & issue
Vol. 20, no. 12
pp. 22028 – 22043

Abstract

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An efficient synthesis of enantiomerically-pure β-aryl-γ-lactams is described. The principal feature of this synthesis is the practical resolution of β-aryl-γ-lactams with (S)-Naproxen. The procedure is based on the Michael addition of nitromethane to benzylidenemalonates, which was easily obtained, followed by the reduction of the γ-nitroester in the presence of Raney nickel and the subsequent saponification/decarboxylation reaction. The utility of this methodology was highlighted by the preparation of enantiomerically-pure (R)- and (S)-Baclofen hydrochloride.

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