Diastereo- and enantioselective hydrogenative aldol coupling of vinyl ketones: design of effective monodentate TADDOL-like phosphonite ligands

J Am Chem Soc. 2008 Mar 5;130(9):2746-7. doi: 10.1021/ja710862u. Epub 2008 Feb 12.

Abstract

We report the first enantioselective reductive aldol couplings of vinyl ketones, which were achieved through the design of a novel monodentate TADDOL-like phosphonite ligand. Specifically, hydrogenation of commercially available methyl vinyl ketone (MVK) or ethyl vinyl ketone (EVK) in the presence of aldehydes 1a-7a using cationic rhodium catalysts modified by chiral TADDOL-like phosphonite ligands AP-I and AP-IV produces aldol adducts 1b-7b and 1c-7c with excellent control of relative and absolute stereochemistry. The absolute stereochemical assignments of the aldol adducts are made in analogy to that determined for the 5-bromophthalimido derivative of aldol adduct 1b and the 2-bromo-5-nitrobenzoate of 3b, which were established by single-crystal X-ray diffraction analysis using the anomalous dispersion method.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Catalysis
  • Crystallography, X-Ray
  • Dioxolanes / chemistry
  • Hydrogenation
  • Ketones / chemical synthesis*
  • Ketones / chemistry*
  • Ligands
  • Methanol / analogs & derivatives
  • Methanol / chemistry
  • Molecular Structure
  • Organometallic Compounds / chemistry
  • Organophosphorus Compounds / chemical synthesis
  • Organophosphorus Compounds / chemistry*
  • Oxidation-Reduction
  • Rhodium / chemistry
  • Stereoisomerism

Substances

  • Dioxolanes
  • Ketones
  • Ligands
  • Organometallic Compounds
  • Organophosphorus Compounds
  • alpha,alpha,alpha',alpha'-tetraaryl-1,3-dioxolane-4,5-dimethanol
  • Rhodium
  • Methanol