[Cu2(HBTC)2(H2O)2(μ2-H2O)] · 2H2O: a new arm-shaped two-dimensional copper coordination polymer having both rhombic cavities and helical-like channels

A new arm-shaped two-dimensional layered complex, [Cu2(HBTC)2(H2O)2(μ2-H2O)] · 2H2O (1) (BTC=1,2,4-benzenetricarboxylate), has been prepared by hydrothermal reaction of Cu(NO3)2 · 3H2O, BTC and triethylamine at 160 °C and characterized by single-crystal X-ray diffraction analysis. The two-dimensional layer of 1 not only consists of regular rhombic cavities but also possesses pseudo-helical-shaped channels. In addition, the hydrogen-bonding and π–π stacking interactions between layers extend 1 into a three-dimensional supramolecular architecture with two differently oriented fashions.