ISSN:
0749-1581
Keywords:
N-Trimethylsilylaminophosphorus compounds
;
13C, 15N, 29Si, 31P NMR
;
Signs of 1J(31P, 15N), 2J(31P,N, 29Si) coupling constants
;
Hahn-echo
;
2D heteronuclear shift correlations
;
Isotope shifts, 1Δ15/14N(31P)
;
Chemistry
;
Analytical Chemistry and Spectroscopy
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
N-Trimethylsilylaminophosphorus compounds containing phosphorus in different oxidation states [P(III) and P(V)] and with different coordination numbers (2, 3 or 4) were studied by 13C, 14N, 29Si and 31P NMR, using a variety of one- and two-dimensional (2D) techniques, including Hahn-echo extended (HEED) pulse sequences. These techniques were demonstrated by the determination of the signs of all coupling constants involving the 1H, 13C, 15N, 29Si and 31P nuclei in bis(trimethylsilyl)aminodimethylphosphane (1). Appropriate experiments, including inverse 2D 1H{15N} correlations, were performed for the other compounds in order to determine the signs of the coupling constants. A geometric dependence of 2J(31P, N, 29Si) was proved for bis(trimethylsilyl)amino(tert-butyl)chlorophosphane (2c), where large negative 2J(31P,29Si) and a small positive 2J(31P,29Si) values, indicate syn and anti orientations, respectively, of the N—Si bond relative to the phosphorus lone pair of electrons. The HEED pulse sequences allow the rapid determination of isotope-induced shifts, 1δ15/14N(31P), as shown for 1, derivatives of 1 and 2c.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/mrc.1260300407
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