1 H and 31 P nuclear magnetic resonance spectra of compounds containing the P III NP V skeleton

The 1 H and 31 P NMR spectra of a series of compounds containing the P III ‐N‐P V skeleton including Cl 2 PNMeP(Z)Cl 2 (ZO or S), Cl 2 P·NMe·P(O)CINMe 2 , P 4 (NMe) 6 Z n (ZS, n = 1−3; ZSe, n = 1), XP(NBu t ) 2 P(Z)X (XCl, ZO or S; XOMe, ZS or Se; XNMe 2 , ZS or Se; XNEt 2 , ZSe), (XO or S), and Ph 2 PNRP(S)Ph 2 (RMe, Et) have been obtained. 1 H‐{ 31 P} double resonance, and in selected cases, 31 P‐{ 1 H, 77 Se} and 31 P‐{ 1 H, 31 P} triple resonance experiments, indicate that 2 J ( P III N P V ) is positive in acyclic compounds, negative in most cyclic or cage compounds, and furthermore, is related to the conformation adopted by the P III ‐N bond.