Synthesis and single crystal structure analysis of 3,3',5,5'-tetramethyl-4,4'-bipyrazolium tetrachlorocobaltate(ii) monohydrate [H2ME4BPZ][CoCl4]·H2O

Abstract

Slow evaporation of a solution of 3,3',5,5'-tetramethyl-4,4'-bipyrazolium chloride ([H₂Me₄bpz]Cl₂) with the cobalt chloride in concentrated aqueous HCl solution yielded block blue crystals and X-ray single crystal structure determination at 100K revealed that the molecule crystallized in the monoclinic system with a P2₁/n space group. The asymmetric units consist of tetrahedral [CoCl₄]^2- anions and tetramethyl bipyrazolium [H₂Me₄bpz]²⁺ dications and one water molecule which are connected through N—H····Cl and N—H····O hydrogen bond networks in the crystal lattice.

Keywords: Crystal structure, Hydrogen bond and crystal engineering