An electrochemical and structural study of the iron silylamides fe[n(sime3)2]2 and

摘要

The bis(trimethyl)silylamido complex Na(THF){Fe[N(SiMe3)2]3} and the disilane tBu3SiSitBu3 were obtained from the reaction of Fe[N(SiMe3)2]3 with the sodium silanide Na(THF)2[SitBu3] in a mixture of benzene and THF. Single crystals of Na(THF){Fe[N(SiMe3)2]3} suitable for X-ray diffraction were grown from the reaction solution at ambient temperature (orthorhombic, C2221, Z = 4). The solid-state structure features a contact-ion pair with two short N-Na contacts. The THF adducts {M(THF)2[N(SiMe3)2]2} reacted with 2,20-bipyridine to give the corresponding complexes {M(2,20bipy)[N(SiMe3)2]2} (M= Mn; Fe). Their structures (M= Fe: orthorhombic, Pca21, Z = 8; M = Mn: orthorhombic, Pbca, Z = 8) feature monomeric units. The cyclic voltammogram of Fe[N(SiMe3)2]3 revealed a reversible redox transition with the potential of.0;523 V (E1=2), which was assigned to the Fe(III)[N(SiMe3)2]3! Fe(II)[N(SiMe3)2].3 redox transition, whereas the compounds {Fe(THF)2[N(SiMe3)2]2} (Eox =.0;379 V) and {Fe(2,20bipy)[N(SiMe3)2]2} (Eox =.0;436 V) featured irreversible oxidation waves. The related manganese bis(trimethylsilyl)amido complexes {Mn(THF)2[N(SiMe3)2]2} (Eox =.0;458 V) and {Mn(2,20bipy)[N(SiMe3)2]2} (Eox =.0513 V) also underwent irreversibile electron transfer processes.