Abstract
The redcution of {Fe(NO)2}9 DNIC, [K-18-crown-6-ether][(SEt)2Fe(NO)2], mainly occurs on Fe and S. The interaction of [Fe(SEt)2…(K+)] is an important factor to stablize the complex. Upon the cation, K+, is removed, the complex immediately transforms to the di-anionic RRE (daRRE), [(-SEt)Fe(NO)2]22-. However, the di-anionic {Fe(NO)2}10 DNIC containing bidentate ligand is stable. Addition of {Fe(NO)2}10 motif to {Fe(NO)2}10 DNIC, [PPN]2[(2-SC2H4S)Fe(NO)2]2, produces [PPN]2[(NO)2Fe(-2-SC2H4S)(-NO)Fe(NO)] instead of daRRE. The Fe K-edge and S K-edge absorption spectra and DFT calculation rationalize the reduction from {Fe(NO)2}9 to {Fe(NO)2}10 and the difference of reduction potentials between monodentate and bidentate {Fe(NO)2}10 DNICs.