SYNTHESIS AND REACTIONS OF AZIDO COMPLEXES OF IRON

Sodium azide reacts with FeH2(dmpe)(2) (1a) dmpe = 1,2-bis(dimethylph osphino)ethane in methanol solution to form FeH(N-3)(dmpe)(2) (3a) an d, finally, Fe(N-3)(2)(dmpe)(2) (2a). The bis(azide) complex may also be generated from FeCl2(dmpe)(2) (4a) by a ligand exchange reaction. T he azide ligand is easily replaced by terminal alkynes to form bisacet yl iron complexes. The X-ray crystal structure of Fe(N-3)(2)(dmpe)(2) (2a) shows that the azide groups are mutually trans and that the N-N-N groups are essentially linear and tilted by approximately 132 degrees with respect to the plane containing the Fe and the four P atoms.