Nuclear magnetic resonance investigation of rotation about phosphorus(V)–nitrogen bonds in aminocyclodiphosph(V)azanes

Keat, R., Rycroft, D. S. and Thompson, D. G. (1980) Nuclear magnetic resonance investigation of rotation about phosphorus(V)–nitrogen bonds in aminocyclodiphosph(V)azanes. Journal of the Chemical Society: Dalton Transactions, 1980(10), pp. 1858-1862. (doi: 10.1039/DT9800001858)

Abstract

Hydrogen-1 n.m.r. data on the cyclodiphosph(V)azanes [R₂N(X)PNBu^t]₂ (R = Me, X = O, S, or Se; R = Et, X = S or Se) and [Me₂N(O)PNR]₂ (R = Ph or CH₂Ph) indicate that rotation about the exo P^V–N bonds is slow on the n.m.r. time scale at ambient or sub-ambient temperatures. In the former series, trans isomers have higher rotational barriers, ΔG_Tc^‡, than analogous cis isomers and these barriers are also greater for trans oxides than analogous sulphides or selenides. The rotational barriers for P^V–N and P^III–N have also been measured for the compounds Me₂NP[NBu^t]₂P(X)NMe₂ (X = S, Se, or MeI), Me₂N(X)P[NBu^t]₂P(Y)Cl (X = S, Y = lone pair; X = O, Y = O), and cis-Me₂N(S)P[NBu^t]₂P(Se)NMe₂. Carbon-13 n.m.r. data obtained at various temperatures on geometrical isomers of [Me₂N(X)PNBu^t]₂ (X = O, S, or Se) indicate that J(PNC) (exo) is much more stereospecific than J(PNCH), especially when X = S or Se.

• Item Type: Articles
• Keywords: Phosphorus chemistry, NMR spectroscopy.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Rycroft, Dr David
• Authors: Keat, R., Rycroft, D. S., and Thompson, D. G.
• Subjects: Q Science > QD Chemistry
• College/School: College of Science and Engineering > School of Chemistry
• Journal Name: Journal of the Chemical Society: Dalton Transactions
• Publisher: The Royal Society of Chemistry
• ISSN: 0300-9246