UNIGE document Scientific Article
previous document  unige:14781  next document
add to browser collection

Chromatographic Resolution, Solution and Crystal Phase Conformations, and Absolute Configuration of tert-Butyl(dimethylamino)phenylphosphine-Borane Complex

Naubron, Jean-Valère
Giordano, Laurent
Fotiadu, Frédéric
Vanthuyne, Nicolas
Roussel, Christian
Buono, Gérard
Published in Journal of Organic Chemistry. 2006, vol. 71, no. 15, p. 5586-5593
Abstract The enantiomers of tert-butyl(dimethylamino)phenylphosphine−borane complex 2 have been separated by HPLC using cellulose tris-p-methylbenzoate as chiral stationary phase. The borane protection could be removed without racemization and the P-configuration of the free aminophosphine 1 has shown to be stable in solution. Infrared (IR) and vibrational circular dichroism (VCD) spectra have been measured in CD2Cl2 solution for both enantiomers. B3LYP/6-31+G(d) DFT calculations allowed a prediction that complex (S)-2 exists as three conformers in equilibrium and computed population-weighted IR and VCD spectra. Predicted and experimental IR and VCD spectra compared very well and indicate that enantiomer (+)-2 has the S absolute configuration. This assignment has been confirmed by an X-ray diffraction study on a single crystal of (+)-2. The crystal structure of enantiomerically pure 2 appears to be very close to the most stable computed conformer which proved to be predominant in solution.
Stable URL https://archive-ouverte.unige.ch/unige:14781
Full text
Article - document accessible for UNIGE members only Limited access to UNIGE
Other version: http://pubs.acs.org/doi/pdf/10.1021/jo0605647

201 hits



Deposited on : 2011-03-18

Export document
Format :
Citation style :