Double salts of copper(I) chloride incorporated hydroxylpyrimidine and tetrazole ligands

Hydrothermal reaction of copper(II) chloride with 2-hydroxypyrimidine generated double salt of [Cu₂Cl(μ₄-pymo)] (1) (Hpymo = hydroxylpyrimidine) while hydrothermal treatment of CuCl₂, NaN₃ and acetonitrile resulted in double salt of [Cu₂(mtta)Cl] (2) (Hmtta = 5-methyltetrazole) in which in situ [2 + 3] cycloaddition reactions of acetonitrile with azide formed mtta ligand. X-ray single crystal structural analyses revealed that 1 shows a two-dimensional layer formed by fusion of one-dimensional structural motifs. The two-dimensional layers in 1 are held together by C-H?Cl hydrogen bonds to form three-dimensional supramolecular array. Compound 2 has a three-dimensional framework constructed from ribbons and [Cu₈Cl₄]⁴⁺ units. Uncommon coordination modes of μ₄-1,2κO:3κN:4κN′ pymo and μ₄-Cl (Cl at the apex of a Cu₄Cl square pyramid) in 1 and μ₄-η¹:η¹:η¹:η¹ mtta in 2 were also observed. The short Cu(I)?Cu(I) distances were found in 1 and 2, indicating the existence of Cu(I)?Cu(I) interactions.