Zur ursache der extremen 31P-NMR-verschiebungen von phosphinidenkomplexen

Abstract

Phosphinidene complexes RP[ML n ] 2 (R = univalent residue; L n M = 16 electron fragment e.g. (CO) 5Cr, Cp(CO) 2Mn) show extremely paramagnetic 31P NMR shifts (884 to 1362 ppm). The values of these NMR shifts are strongly correlated with the energy of the electroic ππ * transition in ▪ π-systems. The large paramagnetic 31P NMR shifts is caused by the small ▪ HOMO-LUMO separation specific for these compounds.