Synthesis and Characterization of (smif)2Mn (n = 0, M = V, Cr, Mn, Fe, Co, Ni, Ru; n = +1, M = Cr, Mn, Co, Rh, Ir; smif =1,3-di-(2-pyridyl)-2-azaallyl)

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Department of Chemistry & Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, United States
Department of Chemistry & Pharmacy, University of Erlangen-Nuremberg, Egerlandstrasse 1, D-91058 Erlangen, Germany
Department of Chemistry, Center for Advanced Scientific Computing and Modeling (CASCaM), University of North Texas, Box 305070, Denton, Texas 76203-5070, United States
Fax: 607 255 4173. E-mail: [email protected]
Cite this: Inorg. Chem. 2011, 50, 24, 12414–12436
Publication Date (Web):November 17, 2011
Copyright © 2011 American Chemical Society
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A series of Werner complexes featuring the tridentate ligand smif, that is, 1,3-di-(2-pyridyl)-2-azaallyl, have been prepared. Syntheses of (smif)2M (1-M; M = Cr, Fe) were accomplished via treatment of M(NSiMe3)2(THF)n (M = Cr, n = 2; Fe, n = 1) with 2 equiv of (smif)H (1,3-di-(2-pyridyl)-2-azapropene); ortho-methylated (oMesmif)2Fe (2-Fe) and (oMe2smif)2Fe (3-Fe) were similarly prepared. Metatheses of MX2 variants with 2 equiv of Li(smif) or Na(smif) generated 1-M (M = Cr, Mn, Fe, Co, Ni, Zn, Ru). Metathesis of VCl3(THF)3 with 2 Li(smif) with a reducing equiv of Na/Hg present afforded 1-V, while 2 Na(smif) and IrCl3(THF)3 in the presence of NaBPh4 gave [(smif)2Ir]BPh4 (1+-Ir). Electrochemical experiments led to the oxidation of 1-M (M = Cr, Mn, Co) by AgOTf to produce [(smif)2M]OTf (1+-M), and treatment of Rh2(O2CCF3)4 with 4 equiv Na(smif) and 2 AgOTf gave 1+-Rh. Characterizations by NMR, EPR, and UV–vis spectroscopies, SQUID magnetometry, X-ray crystallography, and DFT calculations are presented. Intraligand (IL) transitions derived from promotion of electrons from the unique CNCnb (nonbonding) orbitals of the smif backbone to ligand π*-type orbitals are intense (ε ≈ 10 000–60 000 M–1cm–1), dominate the UV–visible spectra, and give crystals a metallic-looking appearance. High energy K-edge spectroscopy was used to show that the smif in 1-Cr is redox noninnocent, and its electron configuration is best described as (smif(−))(smif(2−))Cr(III); an unusual S = 1 EPR spectrum (X-band) was obtained for 1-Cr.

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CIF files for 1-M (M = V, Cr, Mn) and 1+-Cr (those for 1-M (M = Fe, Co, Ni) and 1+-Co can be found in the Supporting Information of ref 48) and additional spectroscopic details and experimental considerations, including JulX fits of all SQUID data. This material is available free of charge via the Internet at

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