In-situ synthesis of a pyrazine-based triazolate ligand towards a Cu6 cluster: Synthesis, crystal structure and magnetic properties

A new Cu6 cluster, [Cu6O2(L)2(OAc)6] (1) (HL = 2-(5-(pyrazin-2-yl)-4H-1,2,4-triazol-3-yl)pyrazine), was been synthesized via the reaction of pyrazine-2-carbonitrile and [Cu2(OAc)4]·2H2O in THF under solvothermal conditions, in which the HL ligand was in situ generated through coupled, rearranged and delaminated processes of pyrazine-2-carbonitrile and hydrazine. The structure of the complex 1 consisted a [Cu6(μ4-O)2]8+ bitetrahedral core. Variable temperature magnetic susceptibility measurements of complex 1 that it has a ground state spin value of S = 0, as the results of significant intramolecular antiferromagnetic interactions.