KRISTALLSTRUKTUR EINES DIMETHYLAMINO(DIFLUOR)SUBSTITUIERTEN PHOSPHOLIDINIUM-KATIONS MIT DER N,N,N′-TRIMETHYLETHYLENDIAMINEINHEIT

Abstract The cations of compounds 1 and 2 exhibit dynamic behaviour in solution at room temperature; the two fluorine atoms cannot be distinguished by 31P n.m.r. spectroscopy.31 P n.m.r. spectra of 2 at −20°C indicate non-equivalence of the fluorine atoms, and the intramolecular exchange process is slowed down. A low temperature X-ray crystal structure analysis of 2 confirms the expected geometry of the cation. The phosphorus atom displays trigonal bipyramidal coordination geometry, with the chelating ligand spanning one equatorial (NMe, P–N 164.4 pm) and one axial (NMe, P–N 198.7 pm) site at phosphorus.