39210-75-8Relevant articles and documents
Tert-butylnitroso complexes. Structural characterization of W(CO)5 (N(O)But) and [CpFe(CO)(PPh3)(N(O)But)]+
Pilato,McGettigan,Geoffroy,Rheingold,Geib
, p. 312 - 317 (2008/10/08)
The new tert-butylnitroso complexes W(CO)5(N(O)But) (1), [CpFe(CO)(PPh3)(N(O)But)]+ (2), [CpRu(PPh3)2(N(O)But)]+ (3), and CpMn(CO)2(N(O)But) (4) have been prepared and spectroscopically characterized. Complexes 1 and 2 have been further defined by crystallographic studies. The nitroso ligands of both complexes are coordinated via the nitrogen atom, and in each case the nitroso ligand is oriented in such a way as to maximize its π bonding to the metal. EHMO calculations on the model complex (W(CO)5(N(O)Me) show that the nitroso molecule acts as a σ-donor, π-acceptor ligand with the LUMO being an antibonding combination of a metal dxz orbital and a NO π orbital. The LUMO is calculated to lie only approximately 0.7 eV above the filled, largely nonbonding dxy, dyz orbitals, giving rise to a low-energy metal-to-ligand charge-transfer transition in the visible spectral region, which accounts for the intense color of these ButN=O complexes.