Replacement of carboxylate bridges in polynuclear nickel pivalates with 2-hydroxy-6-methylpyridine anions

Structural Diversity of Nickel and Manganese Chloride Complexes with Pyridin-2-One

“…Ag(I) ions are in an octahedral environment of four bridging and two terminal Hhp molecules. Hmhp molecules ligated in the 2.2 fashion contribute to the design of hexanuclear nickel cages in some nickel benzoato and pivalato complexes [57,58]. The same ligation of Hmhp was found in a dodecanuclear nickel-phosphonate cluster [59].…”

“…Molecules 2020, 25, x FOR PEER REVIEW 14 of 23 A µ2-oxygen ligation of Hhp is well documented in the dinuclear copper(II) halides or acetate [36,54] and silver(I) complexes [55,56]. In nickel compounds, only Hhp derivatives-Hchp or Hmhpwere observed as neutral organic O-donor bridging ligands, which in cooperation with other bridging anions connects metal ions in hexa- [57,58], nona- [27] and dodecanuclear [20,59] clusters. Copper ions in dinuclear compounds are linked by two Hhp molecules [36,54], while three molecules are involved in a bridging coordination to a pair of 3d metal ions only in a vanadium complex of Hmhp [79].…”

Synthesis, structure, and magnetic properties of new pyridonate–pivalate nickel(II) complex, [Ni11(OH)2(mhp)8(Piv)10(HCO2)2(H2O)2(Hmhp)2(HPiv)2] (mhp = 6-methyl-2-pyridonate), containing formate bridges

“…Recently we have shown that interaction between known nonanuclear antiferromagnetic nickel(II) complex [Ni 9 (OH) 6 (Piv) 12 (HPiv) 4 ] (1) [12] and 2-hydroxy-6-methylpyridone (Hmhp) in MeCN results in metal core degradation and formation of hexanuclear complex [Ni 6 (μ 3 -OH) 2 (mhp) 2 (Piv) 10 (μ-H 2 O) 2 (Hmhp) 2 (HPiv) 2 ]; its further heating at 70°C leads to metal core "folding" in the newly formed complex [Ni 6 (μ 3 -OH)(mhp) 5 (Piv) 6 (Hmhp)]. By contrast, the replacement of MeCN solvent by a THF-EtOH mixture at lower temperature (50°C) leads to metal core enlarging followed by formation of decanuclear cluster [Ni 10 (μ 3 -O) 2 (μ 3 -OH) 4 (μ-Piv) 6 (mhp) 6 (EtOH) 6 ]· 2H 2 O [13]. Unusual dependence of the product composition of this reaction on the synthesis conditions (solvent and temperature) stimulated further research.…”