Jean-Pierre Albrand

Calculation of the 1J(PP) angular dependence in P2H4

Abstract Using the results obtained from an MO SCF ab initio calculation on P 2 H 4 in four different conformations, the 1 J (PP) NMR coupling constants have been calculated. The 1 J (PP) values are highly dependent upon the rotational angle φ (−238.0 Hz in the eclipsed conformation, 10.9 Hz in the staggered one). The shape of the theoretical 1 J (PP) plot seems to be in good agreement with experimentally measured 1 J (PP) values.

Structure, 31P and 13C chemical shift anisotrophy of (CH3)3P, (CH3)3PO, (CH3)3PS and (CH3)3PSe as determined by liquid crystal NMR spectroscopy

Abstract The 13 P and 13 C spectra of the triply 13 C labelled molecules (CH 3 ) 3 P, (CH 3 ) 3 PO, (CH 3 ) 3 PS and (CH 3 ) 3 PSe oriented in a nematic phase are reported. The CPC bond angles have been measured. The 13 P chemical shift tensor shows a large anisotropy except in the case of (CH 3 ) 3 P. The abnormal large value observed for the PSe bond length suggests a large anisotropy of the 1 J (PSe) spin coupling.

NMR spectral analysis of partially oriented hexaphenylcyclohexaphosphine. Relation between 1J(PP) NMR coupling and streochemistry

Abstract The NMR spectral analysis of (PC6H5)6 oriented in a nematic phase is reported. The ring conformation obtained is in good agreement with the X-ray structure data. The 1J(PP) coupling constant (−106 Hz) supports the rotational dependence around the PP bond previously suggested from experimental and theoretical studies.

Assignment of meso and (±) diastereoisomers of diphosphines using 31P nuclear magnetic resonance spectroscopy in a chiral solvent

The assignment of the n.m.r. peaks due to the (±) and meso forms of 1,2-diphenyldiphosphine has been made possible by recording their 31P n.m.r. spectra in an optically active solvent at 40 and 111 MHz.