1,3-Sigmatropic Hydrogen Shift in 3-Amino-1H-1,2,4-Triazole During the Complexation of this Ligand with Cobalt (II) Ion, Single Crystal Structure of a New Trinuclear Co(II) 1,2,4-Triazole Complex

Abstract

[Co3(ATR)6(H2O)6](NO3)6·2H2O (ATR = 3-amino-4H-1,2,4-triazole) was obtained from the reaction of 3-amino-1H-1,2,4-triazole with Co(NO3)2·6H2O. 3-amino-H-1,2,4-triazole was changed to 3-amino-4H-1,2,4-triazole with a 1,3-sigmatropic hydrogen shift during the reaction. The crystal structure of [Co3(ATR)6(H2O)6](NO3)6·2H2O consists of centrosymmetric trinuclear units, cation is located in the center of symmetry coinciding with Co(1) atom position. There are three bridging 3-amino-4H-1,2,4-triazole between the internal and terminal cobalt ions. Crystal data for complex at 100 K: monoclinic, space group P 21/n, a = 13.2308(12) A, b = 12.2167(10) A, c = 14.3954(12) A, β = 113.348(5)°, V = 2136.3(3) A3, Z = 2, R 1 = 0.0550. Masoumeh Tabatabaee*, Mahboubeh A. Sharif, Mitra Ghassemzadeh, Mahmoud Shariyari [Co3(ATR)6(H2O)6](NO3)6·2H2O (ATR = 3-amino-4H-1,2,4-triazole) was obtained from the reaction of 3-amino-1H-1,2,4-triazole with Co(NO3)2·6H2O.