Chlorocadmate(II) salts of two 1,2,4-triazolo-[1,5-a]pyrimidine derivatives

The crystal structure of the ionic compounds (tpH)n[CdnCl3n] and (dmtpH)2[CdCl4] · 2H2O is described, where tp = 1,2,4-triazolo-[1,5-a]pyrimidine and dmtp = 5,7-dimethyl-1,2,4-triazolo-[1,5-a]pyrimidine. Both compounds are monoclinic, space groups P21/c and C2/c, respectively. Unit cell parameters are a = 13.7860(7), b = 9.4013(5), c = 17.6679(9) Å, β = 98.672(1)° for the first compound and a = 11.7543(7), b = 12.6823(7), c = 6.6836(4) Å, β = 96.710(1)° for the second. In both cases, the heterocycles are protonated at the nitrogen atom at position 3. For dmtp, the charge of the cation is neutralized by the simple tetrahedral [CdCl4]2− anion, whereas for tp, a polymeric [CdnCl3n]n− anion is present, formed by aligned face-sharing CdCl6 octahedra.