ASYMMETRIC HYDROGENATION CATALYZED BY AMINOPHOSPHINE-PHOSPHINITERHODIUM COMPLEXES DERIVED FROM NATURAL AMINOALCOHOLS AND X-RAY CRYSTAL STRUCTURE OF (1,5-CYCLOOCTADIENE)-(S)-N-(DIPHENYLPHOSPHINO)-2-DIPHENYLPHOSPHINOXYMETHYLPYRROLIDINERHODIUM(I) PERCHLORATE

Article abstract of DOI:10.1016/0022-328X(83)80246-0

From the cheap and readily available amino alcohols (S)-pyrrolidinemethanol ((S)-prolinol), and (S)-α-N-ethyl-aminobutanol, we have obtained two new aminophosphine-phosphinite ligands: (S)-N-(diphenylphosphino)-2-diphenylphosphinooxymethylpyrrolidine ((S)-Prolophos) and (S)-1-diphenylphosphinoxy-2-N-ethyl-N-diphenylphosphinoaminobutane ((S)-Butaphos).The rhodium(I) complexes of these phosphines act as efficient homogeneous hydrogenation catalysts at ambient temperature and pressures for dehydro N-acetyl amono acids, dehydro N-benzoyl amino acids and itaconic acid.An X-ray diffraction study of the complex *THF has been shown that the crystals belong to the monoclinic space group P2₁ with a 10.680(2), b 10.448(2), c 18.207(3) Angstroem and β 104.97(1)^o.Refinements based on 2105 significant counter reflections led to a final R value of 0.060.The cation is in a distorted square planar geometry, the rhodium atom being bound to the two phosphorus atoms and to the two double bonds of the diene molecule.