A structural comparison of some amine- and thione-substituted triazoles

A series of amine- and thione-substituted triazoles have been synthesized and their structures determined by single-crystal X-ray diffraction methods. The compounds differ in the identity of the amine- and alkyl-substituents on the triazole ting. Crystal data for 4- furfuralideneamino-3-methyl-4,5-dihydro-1H-1,2,4-triazole-5-thione, C₈H₈N₄OS: triclinic, space group P1, Z=2, a=10.490(2) Å, b=10.700(2) Å, c=4.2185(8) Å, α=92.68(2)°, β=90.17(2)°, γ=92.61(1)°, V=472.5(1) ų, R(F)=0.040 for 151 variables and 1056 observations (I > 3σ(I)); 4- furfuralideneamino-3-ethyl-4,5-dihydro-1H-1,2,4triazole-5-thione, C₉H₁₀N₄OS: triclinic, space group P1, Z=2, a=8.366(3) Å, b=9.296(2) Å, c=7.953(2) Å, α=113.72(2)°, β=108.54(3)°, γ=84.94(3)°, V=536.3(3) Å3, R(F)=0.037 for 136 variables and 1126 observations (I > 3σ(I)); 4- furfuralideneamino-3-propyl-4,5-dihydro-1 H-1,2,4-triazole-5-thione, C₁₀H₁₂N₄OS: triclinic, space group P1, Z=2, a=9.149(3) Å, b=9.177(2) Å, c=8.045(4) Å, α=110.11(2)°, β=114.52(3)°, γ=86.44(2)°, V=574.5(4) ų, R(F)=0.040 for 145 variables and 1414 observations (I > 3σ(I)); 4-(2- acetylpytidyleneamino)-3-ethyl-4,5-dihydro-1H1,2,4-triazole-5-thione, C₁₁H₁₃N₅S: triclinic, space group P1, Z=2, a=7.736(3) Å, b=11.752(4) Å, c=7.219(2) Å, α=93.68(3)°, β=106.26(3) Å, γ=91.04(3)°, V=628.3(4) ų, R(F)=0.043 for 154 variables and 1224 observations (I > 3σ(I)). The molecules show substantial variations in conformation as well as in crystal packing. The differences in molecular structure are discussed in terms of the potential of the molecules to act as bidentate ligands towards metal ions.