5149-08-6Relevant articles and documents
Groups 5 and 6 terminal hydrazido(2-) complexes: Nβ substituent effects on ligand-to-metal charge-transfer energies and oxidation states
Tonks, Ian A.,Durrell, Alec C.,Gray, Harry B.,Bercaw, John E.
supporting information; experimental part, p. 7301 - 7304 (2012/06/16)
Brightly colored terminal hydrazido(2-) (dme)MCl3(NNR 2) (dme = 1,2-dimethoxyethane; M = Nb, Ta; R = alkyl, aryl) or (MeCN)WCl4(NNR2) complexes have been synthesized and characterized. Perturbing the electronic environment of the β (NR 2) nitrogen affects the energy of the lowest-energy charge-transfer (CT) transition in these complexes. For group 5 complexes, increasing the energy of the Nβ lone pair decreases the ligand-to-metal CT (LMCT) energy, except for electron-rich niobium dialkylhydrazides, which pyramidalize Nβ in order to reduce the overlap between the Nb=N α π bond and the Nβ lone pair. For W complexes, increasing the energy of Nβ eventually leads to reduction from formally [WVI≡N-NR2] with a hydrazido(2-) ligand to [WIV=N=NR2] with a neutral 1,1-diazene ligand. The photophysical properties of these complexes highlight the potential redox noninnocence of hydrazido ligands, which could lead to ligand- and/or metal-based redox chemistry in early transition metal derivatives.
Photochemical generation of nitrenium ions from protonated 1,1-diarylhydrazines
Winter, Arthur H.,Thomas, Selina I.,Kung, Andrew C.,Falvey, Daniel E.
, p. 4671 - 4674 (2007/10/03)
(Chemical Equation Presented) Laser flash photolysis experiments, chemical trapping studies, and time-dependent density functional theory calculations demonstrate that photolysis of protonated 1,1-diarylhydrazines generates N,N-diarylnitrenium ions.
