Influence of the trans Substituent on N2 Bonding in Iron(ii)-Phosphane Complexes: Structure, Synthesis, and Properties of the Monomeric Adducts trans-[FeXN2 (depe)2 ]BPh4 , X=Cl, Br

Angew Chem Int Ed Engl. 1998 Apr 3;37(6):815-817. doi: 10.1002/(SICI)1521-3773(19980403)37:6<815::AID-ANIE815>3.0.CO;2-6.

Abstract

Not a dimer but a monomer was found in the X-ray structure analysis of the complex "trans-[{FeCl(depe)2 }2 (µ-N2 )](BPh4 )2 " (depe=Et2 PCH2 CH2 PEt2 ). The complexes [FeXN2 (depe)2 ]BPh4 (X=Cl, Br; structure of the cation for X=Cl shown on the right) are much less stable than the analogous hydride compounds and undergo N2 exchange at room temperature even in the solid state.

Keywords: Iron; Moessbauer spectroscopy; N2 complexes; Nitrogen fixation; P ligands.