DFT calculations form the basis of a model capable of predicting the air stability of phosphines. The sensitivity of 18 primary phosphines is accounted for; the model also predicts the trend of increasing stability from phenylphosphine to triphenylphosphine. There is evidence that the radical cation SOMO energy for each corresponding phosphine may be key to its air stability/sensitivity.

No abstract

No rings of fire! Enantiopure primary phosphanes have been developed which are remarkably stable to air oxidation in both solid and solution states (see example). This new class of stable ligand synthon appears to owe its stability to conjugation in their aryl backbones with the extended π ring system. Even one extra ring is good enough.

Abstract:The monometallic pseudo-octahedral complex, [Co(H 2 O) 2 (CH 3 COO) 2 (C 5 H 5 N) 2 ], is shown to exhibit slow magnetic relaxation under an applied field of 1500 Oe. The compound is examined by a combination of experimental and computational techniques in order to elucidate the nature of its electronic structure and slow magnetic relaxation. We demonstrate that any sensible model of the electronic structure must include a proper treatment of the first-order orbital angular momentum, and we find that the slow magnetic relaxation can be well described by a two-phonon Raman process dominating at high temperature, with a temperature independent quantum tunnelling pathway being most efficient at low temperature.