Phosphorus proton coupling

Gordon, M., Griffin, C. E. Solvent Dependence of Geminal Phosphorus-Proton Coupling Constants in Benzylphosphonium Salts. J. Chem. Phys. 41, 2570 (1964). 

Typical one-bond phosphorus-proton coupling constants... 

Four-bond phosphorus-proton couplings V(PH) in allenes are reported in Ref. 163 for allenic phosphineoxides (phosphonylallenes) 256-259, 32 and allenic phosphines (phosphinylallenes) 260-263,130. 

For the phosphinylallenes, on the other hand, correlations of V(PH) and the Hammett small sample of phosphinylallenes 260-263,130 the four-bond phosphorus-proton coupling may be described by Equation 140 - —0.9158) using a DSP approach. 

Compound 1 contains one phosphorus atom, so that the broad-band proton decoupled spectrum is extremely simple it consists of only one line at 8.5 ppm. This spectrum is shown in Fig. 22, together with the proton-coupled spectrum. 

The proton-coupled spectrum is much more informative. We can see immediately which protons show a measurable coupling with the phosphorus atom, because the pattern is clearly identifiable as two triplets separated by 28.7 Hz. This, as we have already seen in Table 1, is the two-bond coupling between the phosphorus and the methine proton. The triplets (intensity 1 2 1)... 

Finally, some typical phosphorus-proton or fluorine couplings through phosphorus or heteroatoms will be discussed. 

It is immiscible in water but is very soluble in common organic solvents, e.g., ethanol, ether, tetrahydrofuran, and benzene. The gaseous infrared spectrum2 exhibits a strong P—H stretch at 2292 cm.-1. Other infrared bands occur at 2920, 1085, 930, 838, 820, and 670 cm.-1. The 31P n.m.r. spectrum shows the expected triplet centered at 131 p.p.m., with a /P H of 193 Hz.f The n.m.r. spectrum consists of a doublet centered at 3.3 p.p.m., with /p H = 194 Hz. Each half of this doublet is further split into a triplet as a result of the coupling of the phosphorus protons with the methylene protons (/ 6 Hz.). The methylene protons exhibit a complex pattern centered at 2.22 p.p.m. ... 

Determine the structure of the phosphorus-containing compound whose molecular formula is C 9H18PBr from the H, l3C, DEPT, and 3IP (both proton-coupled and proton-decoupled). 

Hz) and the phosphinite phosphorus nucleus (9.9 Hz). In the phosphorus spectra the expected couplings are with rhodium, the mutual phosphorus coupling and in the proton coupled spectra the proton coupling for the phosphorus trans to it. 

The possibility of using I3C-NMR spectroscopy to assist in assigning the geometry of bis-phosphine transition metal complexes has attracted the attention of several groups (80, 86-90). The examination of the PMR spectra of such complexes and analysis of the resulting AA XnXJ, spectra has proved valuable (91) but has the disadvantage that it is limited to systems in which the phosphorus atom is attached to methyl, methoxy, or methylene or to related groups in which the protons couple to phosphorus but not to other protons. The condition for the observation of a 1 2 1 triplet (usually associated with trans phosphine molecules) in the proton resonance spectrum is... 

The AA component in the 19F spectrum of (MeSi)2(C6F4)3 presumably has the shape shown in Fig. 9 due to additional H-F coupling as would be expected from this, complex splitting of the methyl resonance is observed in the proton spectrum. The 19F NMR spectrum of P2(C6F4)3 exhibits a symmetrical doublet in the AA component due to phosphorus-fluorine coupling, each half of the doublet being identical to the XX component Jnp-i<>F = 60.2 Hz. 

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