Diiron-aminocarbyne complexes with amine or imine ligands: C–N coupling between imine and aminocarbyne ligands promoted by tolylacetylide addition to [Fe 2{μ-CN(Me)R}(μ-CO)(CO)(NH [dbnd]CPh 2)(Cp) 2][SO 3CF 3

Abstract

A terminally coordinated CO ligand in the complexes [Fe 2{μ-CN(Me)R}(μ-CO)(CO) 2(Cp) 2][SO 3CF 3] (R = Me, 1a; R = Xyl, 1b; Xyl = 2,6-Me 2C 6H 3), is readily displaced by primary and secondary amines (L), in the presence of Me 3NO, affording the complexes [Fe 2{μ-CN(Me)R}(μ-CO)(CO)(L)(Cp) 2][SO 3CF 3] (R = Me, L = NH 2Et, 4a; R = Xyl, L = NH 2Et, 4b; R = Me, L = NH 2Pr i , 5a; R = Xyl, L = NH 2Pr i , 5b; R = Xyl, L = NH 2C 6H 11, 6; R = Xyl, L = NH 2Ph, 7; R = Xyl, L = NH 3, 8; R = Me, L = NHMe 2, 9a; R = Xyl, L = NHMe 2, 9b; R = Xyl, = NH(CH 2) 5, 10). In the absence of Me 3NO, NH 2Et gives addition at the CO ligand of 1b, yielding [Fe 2{μ-CN(Me)(Xyl)}(μ-CO)(CO){C(O)NHEt}(Cp) 2] ( 11). Carbonyl replacement is also observed in the reaction of 1a– b with pyridine and benzophenone imine, affording [Fe 2{μ-CN(Me)R}(μ-CO)(CO)(L)(Cp) 2][SO 3CF 3] (R = Me, L = Py, 12a; R = Xyl, L = Py, 12b; R = Me, L = HN CPh 2, 13a; R = Xyl, L = HN CPh 2, 13b). The imino complex 13b reacts with p-tolylacetylide leading to the formation of the μ-vinylidene-diaminocarbene compound [Fe 2{μ-η 1:η 2- C C(Tol)C(Ph) 2N(H)CN(Me)(Xyl){(μ-CO)(CO)(Cp 2)] ( 15) which has been studied by X-ray diffraction.