Five-Coordinate Low-Spin {FeNO}7 PNP Pincer Complexes

The synthesis and characterization of air-stable cationic mono nitrosonium Fe(I) PNP pincer complexes of the type [Fe(PNP)(NO)Cl](+) are described. These complexes are obtained via direct nitroslyation of [Fe(PNP)Cl-2] with nitric oxide at ambient pressure. On the basis of magnetic and EPR measurements as well as DFT calculations, these compounds were found to adopt a low-spin d(7) configuration and feature a nearly linear bound NO ligand suggesting (FeNO+)-N-I rather than (FeNO center dot)-N-II character. X-ray structures of all nitrosonium Fe(I) PNP complexes are presented. Preliminary investigations reveal that [Fe(PNPNH-iPr)(NO)(Cl](+) efficiently catalyzes the conversion of primary alcohols and aromatic and benzylic amines to yield mono N-alkylated amines in good isolated yields.