One-pot synthesis of Ni(II) and Fe(III) complexes: In situ formation of 2-pyridinemethanol from 2-pyridinecarboxaldehyde

A cubane-like tetranuclear nickel(II) compound [Ni4(L)4Cl4(H2O)3(C2H5OH)]·H2O (1) and a binuclear iron(III) compound Fe2(L)2Cl4 (2) (HL = 2-pyridinemethanol) have been prepared by solvothermal reaction of metal chloride and 2-pyridinecarboxaldehyde in C2H5OH, in which 2-pyridinecarboxaldehyde was in situ reduced to 2-pyridinemethanol. The single crystal X-ray diffraction analysis suggests that the cluster core of [Ni4(μ3-O)4] in 1 is formed by four Ni(II) and four alkoxide oxygen atoms at alternating corners, and the binuclear iron complex 2 is almost co-planar structure with alkoxide oxygen atom in μ2-mode. The magnetic studies reveal the ferromagnetic behavior for 1 and the anti-ferromagnetic interaction for 2.

The solvothermal reaction of NiCl2 and FeCl3 with 2-pyridinecarboxaldehyde in C2H5OH solution at 100 °C can afford two types of polynuclear compounds in which the ligand 2-pyridinemethanol derived from the reduction of the 2-pyridinecarboxaldehyde and the alkoxide oxygen atoms acts as μ3- and μ2-linkage, respectively.Figure optionsDownload as PowerPoint slideResearch Highlights
► Two Ni2+ and Fe3+ complexes were obtained by in-situ solvothermal reaction.
► 2-pyridinecarboxaldehyde was in situ reduced to 2-pyridinemethanol.
► Ni complex is cubane-like formed by four Ni2+ and four alkoxide O atoms in μ3-mode.
► Fe complex is co-planar with alkoxide O atoms in μ2-mode.
► They display ferromagnetic and anti-ferromagnetic interactions, respectively.