69010-95-3Relevant academic research and scientific papers
Homoleptic cobalt and copper phenolate A2[M(OAr)4] compounds: The effect of phenoxide fluorination
Buzzeo, Marisa C.,Iqbal, Amber H.,Long, Charli M.,Millar, David,Patel, Sonal,Pellow, Matthew A.,Saddoughi, Sahar A.,Smenton, Abigail L.,Turner, John F. C.,Wadhawan, Jay D.,Compton, Richard G.,Golen, James A.,Rheingold, Arnold L.,Doerrer, Linda H.
, p. 7709 - 7725 (2004)
Two series of homoleptic phenolate complexes with fluorinated aryloxide ligands A2[M(OAr)4] with M = Co2+ or Cu 2+, OAr- = (OC6F5)- (OArF) or {3,5-OC6H3(CF3) 2}- (OAr′), A+ = K (18-crown-6) +, Tl+, Ph4P+, Et3HN +, or Me4N+ have been synthesized. Two related complexes with nonfluorinated phenoxide ligands have been synthesized and studied in comparison to the fluorinated aryloxides demonstrating the dramatic structural changes effected by modification of OPh to OArF. The compounds {K(18-crown-6)}2[Cu(OArF)4], 1a; {K(18-crown-6)}2[Cu(OAr′)4], 1b; [Tl 2Cu(OArF)4], 2a; [Tl2Cu(OAr′) 4], 2b; (Ph4P)2[Cu(OArF) 4], 3; (nBu4N)2[Cu(OAr F)4], 4; (HEt3N)2[Cu(OAr F)4], 5; {K(18-crown-6)}2[Cu 2(μ2-OC6H5)2(OC 6H5)4], 6; {K(18-crown-6)} 2[Co(OArF)4], 7a; {K(18-crown-6)} 2[Co(OAr′)4], 7b; [Tl2Co(OAr F)4], 8a; [Tl2Co(OAr′)4], 8b; (Me4N)2[Co(OArF)4], 9; [Cp 2Co]2[Co(OAr′)4], 10; and {K(18-crown-6)}2[Co2(μ2-OC6H 5)2(OC6H5)4], 11, have been characterized with UV-vis and multinuclear NMR spectroscopy and solution magnetic moment studies. Cyclic voltammetry was used to study 1a, 1b, 7a, and 7b, X-ray crystallography was used to characterize 1b, 3, 4, 5, 6, 7a, 7b; 10, and 11. The related [MX4]2- compound (Ph 4P)2[Co(OArF)2Cl2], 12, has also been synthesized and characterized spectroscopically, as well as with conductivity and single-crystal X-ray diffraction. Use of fluorinated aryloxides permits synthesis and isolation of the mononuclear, homoleptic phenolate anions in good yield without oligomerized side products. The reaction conditions that result in homoleptic 1a and 7a with OArF upon changing the ligand to OPh result in μ2-OPh bridging phenoxides and the dimeric complexes 6 and 11. The [M(OArF)4]2- and [M(OAr′)4]2- anions in 1a, 1b, 3, 4, 5, 7a, 7b, 9, and 10 demonstrate that stable, isolable homoleptic phenolate anions do not need to be coordinatively or sterically saturated and can be achieved by increasing the electronegativity of the ligand.
Spin-state tuning at pseudotetrahedral d7 ions: Examining the structural and magnetic phenomena of four-coordinate [BP3]Co II-X systems
Jenkins, David M.,Peters, Jonas C.
, p. 7148 - 7165 (2007/10/03)
Electronic structure, spin-state, and geometrical relationships for a series of pseudotetrahedral Co(II) aryloxide, siloxide, arylthiolate, and silylthiolate complexes supported by the tris(phosphino)borate [BP3] ligands [PhBP3] and [PhBPiPr3] ([PhB(CH 2PPh2)3]- and [PhB(CH 2PiPr2)3]-, respectively) are described. Standard 1H NMR, optical, electrochemical, and solution magnetic data, in addition to low-temperature EPR and variable temperature SQUID magnetization data, are presented for the new cobalt(II) complexes [PhBP3]CoOSiPh3 (2), [PhBP3]CoO(4- tBu-Ph) (3), [PhBP3]CoO(C6F5) (4), [PhBP3]CoSPh (5), [PhBP3]CoS-(2,6-Me2-Ph) (6), [PhBP3]CoS(2,4,6-iPr3-Ph) (7), [PhBP 3]CoS(2,4,6-tBu3-Ph) (8), [PhBP 3]CoSSiPh3 (9), [PhBP3]CoOSi(4-NMe 2-Ph)3 (10), [PhBP3]CoOSi(4-CF 3-Ph)3 (11), [PhBP3]CoOCPh3 (12), [PhBPiPr3]-CoOSiPh3 (14), and [PhBP iPr3]CoSSiPh3 (15). The low-temperature solid-state crystal structures of 2, 3, 5-10, 12, and 15 are also described. These pseudotetrahedral cobalt(II) complexes are classified as featuring one of two limiting distortions, either umbrella or off-axis. Magnetic and spectroscopic data demonstrate that both S = 1/2 and S = 3/2 ground-state electronic configurations are accessible for the umbrella distorted structure type, depending on the nature of the X-type ligand, its denticity (η1 versus η3), and the tripodal phosphine ligand employed. Off-axis distorted complexes populate an S = 1/2 ground-state exclusively. For those four-coordinate complexes that populate S = 1/2 ground states, X-ray data show two Co-P bond distances that are invariably shorter than a third Co-P bond. The pseudotetrahedral siloxides 2, 10, and 11 are exceptional in that they display gradual spin crossover in the solid state. The diamagnetic cobalt(III) complex {[PhBP3]CoOSiPh3}{BAr 4} ({16}{BAr4}) (Ar = Ph or 3,5-(CF3) 2-C6H3) has also been prepared and structurally characterized. Accompanying electronic structure calculations (DFT) for complexes 2, 6, and {16}+ support the notion of a close electronic structure relationship between these four-coordinate systems and octahedral, sandwich, and half-sandwich coordination complexes.
Non-oxo Chemistry of Manganese in High Oxidation States. Part 1. Mononuclear tert-Butylimido Compounds of Manganese-(VII) and -(VI)
Danopoulos, Andreas A.,Wilkinson, Geoffrey,Sweet, Tracy K. N.,Hursthouse, Michael B.
, p. 1037 - 1050 (2007/10/02)
The interaction of manganese(III) chloride in acetonitrile with NHR(SiMe3) (R = Bu-t or CMe2CH2Me) gave the manganese(VII) species Mn(NR)3Cl as thermally and air-stable green crystals.The chlorine atom in Mn(NBu-t)3Cl 1 has been substituted by Br, OC(O)R (R = Me or CF3), OC6X5 (X = F or Cl), OCH(CF3)2, SC6F5, C6F5 or NHBut by use of SiMe3Br and the silver, thallium or lithium salts of other reagents.Interaction of compound 1 with Ag(O3SCF3) or AgPF6 and NH2Bu-t gave the salts of the cation (1+), with Li(NHBu-t) under selected conditions gave the paramagnetic manganese(VI) analogues of the manganate(VI) anion, 2 , and with HCl gave Mn(NBu-t)2(NHBu-t)Cl2, the reaction being reversed by addition of pyridine.Unstable compounds, e.g.Mn(NBu-t)3(C6F5) and Mn(NBu-t)3(NHBu-t), were characterised spectroscopically.The mechanism of the formation of 1 is discussed together with a mechanism accounting for the instability of compounds where the X-group has β-H atoms as in Mn(NBu-t)3. β-Hydrogen transfer to a NBut group to give a manganese(V) dimer 2 occurs with the formation of ketones from alkoxides; for alkyls decomposition appears to involve homolysis of the Mn-C bond and a radical pathway.The crystal structures of the compounds Mn(NBu-t)3X, X = OC(O)Me, OC6F5, SC6F5, Y, Y = CF3SO3 or PF6 and 2 have been determined.In all the compounds the manganese atom has distorted tetrahedral geometry.In the first three the Mn-N(imido) bond lengths are 1.664(3)-1.673(9) Angstroem and the Mn-N-C angles 139.9(2) to 144,6(3) deg, indicating partial multiple-bond character.The Mn-X distances, 1.91(3), 1.896(2) and 2.289(1) Angstroem respectively indicate single bonds.In the cationic compounds the Mn-N(imido) distances are 1.531(8)-1.655(8) Angstroem, with Mn-N-C angles of 135.8(6)-170.2(9) deg, suggesting more uneven distribution of the Mn-N multiple bonding, although these structures were less precisely determined due to disorder.In the manganate(VI) anion the Mn-N(imido) lenghts are longer, 1.746(3)-1.749(3) Angstroem, as expected.
