Optically pure 1,2-bis[(o-alkylphenyl)phenylphosphino]ethanes and their use in rhodium-catalyzed asymmetric hydrogenations of α-(acylamino)acrylic derivatives

Yoshiyuki Wada, Tsuneo Imamoto, Hideyuki Tsuruta, Kentaro Yamaguchi, Ilya D. Gridnev

Research output: Contribution to journalArticlepeer-review

40 Citations (Scopus)

Abstract

Optically pure (S,S)-1,2-bis[(o-alkylphenyl)-phenylphosphino]ethanes 1a-d were prepared in four steps from phenyldichlorophosphine via phosphine-boranes as the intermediates. The rhodium complexes 5a-d of these diphosphines were used for the asymmetric hydrogenations of α-(acylamino)-acrylic derivatives including β-disubstituted derivatives. Markedly high enantioselectivity (78→99%) was observed for the reduction of β-monosubstituted derivatives. β-Disubstituted derivatives were also reduced in considerably high enantioselectivity (up to 90%). The single crystal X-ray analysis of the rhodium complex 5c of (S,S)-1,2-bis[phenyl(5′,6′,7′,8′- tetrahydronaphthyl)phosphino]ethane (1c) revealed its δ-type structure with face orientation of the two tetrahydronaphthyl groups and edge orientation of the two phenyl groups. This conformation corresponds to that of the rhodium complex of 1,2-bis[(o-methoxyphenyl)phenylphosphino]ethane (DIPAMP); the rhodium complex of (R,R)-DIPAMP, whose chirality at phosphorus is opposite that of 5c, exhibits a λ-type structure with the face orientation of the two o-methoxyphenyl groups and the edge orientation of the two phenyl groups. The conformational similarity of these rhodium complexes as well as the stereochemical outcome in the asymmetric hydrogenations means that the coordinative interaction of the methoxy group of DIPAMP with rhodium metal is not the main factor that affects asymmetric induction.

Original languageEnglish
Pages (from-to)777-788
Number of pages12
JournalAdvanced Synthesis and Catalysis
Volume346
Issue number7
DOIs
Publication statusPublished - 2004 Jul 1

Keywords

  • Asymmetric catalysis
  • Asymmetric hydrogenation
  • Enantioselectivity
  • P-stereogenic ligands
  • Rhodium catalysts

ASJC Scopus subject areas

  • Catalysis
  • Organic Chemistry

Fingerprint Dive into the research topics of 'Optically pure 1,2-bis[(o-alkylphenyl)phenylphosphino]ethanes and their use in rhodium-catalyzed asymmetric hydrogenations of α-(acylamino)acrylic derivatives'. Together they form a unique fingerprint.

Cite this