Computational and experimental approaches to the molecular structure of the HCl adduct of Me3PO

Abstract

The reaction of anhydrous HCl(g) with trimethyl phosphane oxide yields trimethylhydroxy phosphonium chloride. A crystal structure analysis showed that the prevalent mesomeric structure in the solid state is the phosphonium chloride ion pair. Ab initio calculations in the gas phase cannot reproduce these findings, whereas higher correlated methods (CISD) and solvation models predict the experimental structure correctly.

Anionic phosph(in)ito (“phosphoryl”) ligands: Non-classical “actor” phosphane-type ligands in coordination chemistry

“…Phosphane oxides have been investigated in strong intermolecular hydrogen bonding with proton H + or Hbonded water molecule that link intermolecularly pairs of P + −O -entities [159][160][161][162][163][164][165][166][167][168]. Triphenylphosphane oxide A c c e p t e d M a n u s c r i p t (TPPO) has been widely exploited [169][170][171] in crystal engineering [172], particularly with regard to the design of hydrogen-bonded co-crystals.…”

Evidence of Phosphonium‐Carbenium Dication Formation in a Superacid: Precursor to Fluorinated Phosphine Oxides

“…The P−O bond length is comparable with that of phosphoric acid (1.548(4) Å), but shorter than a typical single P−O bond . A possible explanation is that the highly polarized P−O sigma‐bond and the two p‐type orbitals of the oxygen atom undergo a negative hyperconjugation with the P−C antibonding orbital . The P−C bond length remains approximately unchanged compared to that of the neutral compound .…”

Synthesis and unexpected halochromism of carbazole-functionalized dithienophospholes

“…It is well known that PQO bonds are strongly polar bonds and better described with the canonical structure P + -O À , which inherently creates the possibility for the oxide species to interact with electrophiles, such as protons, as confirmed by Pietschnig and co-workers for Me 3 PO and HCl. 12 In fact, we have also recently reported the change in the photo-physics of acylated dithienophosphole oxides in the presence of Lewis acids, such as BF 3 , that are based on similar interactions. 13 Our studies could clearly show that the BF 3 coordinates to the PQO group rather than the CQO group that was also present in the molecules.…”