[(Tmp)Co₂L] Complexes through Preassembly on 2,6‐Diformyl‐ and 2,6‐Bis(benzylimino)‐4‐methylphenolate Templates

Abstract

The reaction of the dinucleating ligand H3L {2‐(2′‐hydroxyphenyl)‐1,3‐bis[4‐(2‐hydroxyphenyl)‐3‐azabut‐3‐enyl]‐1,3‐imidazolidine} with Co(OAc)2·4H2O and NaN3 in MeOH produces the methoxide‐bridged dicobalt complex [CoIII2(μ‐OMe)L(N3)2] (1) under aerobic conditions. If the reaction occurs in the presence of either 2,6‐diformyl‐4‐methylphenolate (dfp–) or 2,6‐bis(benzyliminomethyl)‐4‐methylphenolate (bip–), a preassembly of the [CoII2(OPh)]3+ units takes place on these templates before coordination with L3– in [CoII2(μ‐dfp)L]·3H2O (2·3H2O) and [CoII2(μ‐bip)L]·3H2O (3·3H2O), respectively. Incorporation of these coligands into the structure leads to stabilization of 3+ and 2+ oxidation states of the cobalt. In complex 2, the CoII ions are engaged in a weak antiferromagnetic interaction. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

Azido, Cyanato, and Thiocyanato Coordination Induced Distortions in Pentacoordinated [CoIIA(bip)]2 (A = NCS–, N3–, or NCO–) Complexes

“…[14] The Co-O distances were 2.085 and 2.057 Å within the Co Figure 5). [14,50] The bidentate N,O chelation from one half of the first bip -ligand to Co II bridging interactions from the phenolate groups in the basal-apical mode result in intermediate III, which finally separates 1-3 from the reaction mixture. A similar type of aggregation reaction of two trinuclear fragments into a hexanuclear unit was described by us for a Ni II 6 complex.…”

Mono and bimetallic CoIII Schiff base complexes: Coordination induced ligand imidazolidine ring cleavage and stabilization

“…In DMF solution, the compound 2 shows a band at 639 nm (e = 271 L mol À1 cm À1 ) and is characteristic of the 1 A 1g -1T 1g transitions for octahedral Co III centers [22]. The ligand ?…”

Synthesis and Characterization of Oligonuclear Ru, Co and Cu Oxidation Catalysts

“…This is in accord with an earlier report, which shows that cobalt complexes prepared from Co II and phenolic ligands are readily converted to Co III complexes. [13] Figure 2. X-ray structure of the cation [Co 2 (bbpmp)(μ-OAc)(μ-OMe)] + from 5 at a 30 % probability level.…”