Phosphorus–nitrogen compounds. Part 59. Aromatic carbon‐13 NMR spectra of phenyl‐substituted cyclotriphosphazatrienes. Second‐order effects with phosphorus‐31 nuclei

Abstract

The I3C NMR spectra were obtained for the geminal series N,P,CI,-,Ph, (n = 2, 4, 6) and for the mono spiro series N,P3Ph2[X(CH,),YICIz (X = Y = 0, n = 2, 3, 4; X = Y = NH, n = 2, 3, 4; X = Y = NMe, n = 2, 3; X = 0, Y = NH, n = 3, 4; X = NH, Y = NMe, n = 2, 3; X = 0, Y = NMe, n = 2). Multiplet structures were observed in the "C NMR spectra of N3P,Ph,[HN(CH,)3NHIClz at 0°C. The complexity of these resonances could be altered by a change in temperature. These observations have been rationalized in terms of second-order interactions with remote phosphorus nuclei, which can be systematically altered with temperature. Inductive and resonance substituent coefficients have been calculated using the dual substituent parameter method from the relative shelding of the metu (C-3) and para (C-4) nuclei in the phenyl ring.

Synthesis and structural studies (1H,13C,31P NMR and X-ray) of new C-bonded cyclotriphosphazenes with heterocyclic substituents from novel phosphinic acid derivatives

“…Much more complex are the { 1 H} 13 C spectra of cyclotriphosphazenes when a symmetry exists in the three phosphorus spin system, [18][19][20][21] as in the case of compounds 2, 4 and 6. They show second-order spectra from which, however, 31 P- 13 C coupling constants can be easily obtained.…”