Oxidation of the octa-(ethyl)diphosphaferrocene

Abstract The octa-(ethyl)-diphosphaferrocene ( 1 ) reacts with NOBF 4 in dichloromethane to yield a polymer ( 2 ) featuring diphosphaferrocene ligands ( 1 ) that bridge [Fe(NO) 2 ] units through their two phosphorus atom lone pairs. The X-ray crystal structure of 2 has been recorded. The formation of the 1-P-fluoro-2,3,4,5-tetra-(ethyl)-phosphole oxide as a by-product demonstrates that phosphaferrocenium ( 2 ) is sensitive towards substitution reaction at iron and nucleophilic attack at phosphorus. Oxidation of 1 with iodine in dichloromethane yielded the corresponding phosphaferrocenium cation [FeI 4 ] − complex ( 4 ) which has been characterized structurally. The formation of 4 probably results from the partial decomposition of the diphosphaferrocenium cation having [I 3 ] − as the counter anion.