ISSN:
0030-4921
Keywords:
Chemistry
;
Analytical Chemistry and Spectroscopy
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
All J(P—H) and J(P—C) values, including signs, have been obtained in acetylenic and propynylic phosphorus derivatives, R2P(X)—C≡C—H and R2P(X)—C≡C—CH3 (X = oxygen, lone pair and R = C6H5, N(CH3)2, OC2H5, N(C6H5)2, Cl) from 1H and 13C NMR spectra. In PIV derivatives the following signs are obtained: 1J(P—C)+, 2J(P—C)+, 3J(P—C)+, 3J(P—H)+, 4J(P—H)—. Linear relations are observed between 1J(P—C), 2J(P—C) and 3J(P—C) versus 3J(P—H), indicating that these coupling constants are mainly dependent on the Fermi contact term, though the other terms of the Ramsey theory do not seem to be negligible for 1J(P—C) and 2J(P—C).In PIII derivatives these signs are: 1J(P—C)- and +, 2J(P—C)+, 3J(P—C)-, 3J(P—H)-, 4J(P—H)+. Only 3J(P—C) and 3J(P—H) reflect a small contribution of the Fermi contact term while in 1J(P—C) and 2J(P—C) this contribution seems to be negligible relative to the orbital and/or spin dipolar coupling mechanisms.
Additional Material:
6 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/mrc.1270070808
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