Ionothermal synthesis of a 3D heterometallic coordination polymer based on the rod shaped copper(II)-sodium(I)-carboxylate secondary building units with a pcu topology

Compound 1(EEIM)NaCu(phth)2],, (1) (EEIM = 1,3-diethylimidazolium and phth = terephthalate) was synthesized by using the mixed ionic liquids of 1-ethyl-3-methylimidazolium tetrafluoroborate [EMIM]-BF4 and chiral 1-ethyl-3-methylimidazolium c-lactate as solvent. The sodium(l) ion deriving from the [EMIM]-BF4 with a small amount of Na(I) impurity incorporated into the structure is unprecedented. Compound 1 is a 3D anionic framework based on a unique rod shaped heterometallic copper(II)-sodium(I)-carboxylate secondary building unit, exhibiting a distorted pcu-(4(12) . 6(3)) topology. It is interesting that the organic template of [EEIM](+) cation formed from an in situ reaction acting as extraframework charge-balancing species occupies the 1D rhombic channels of the 3D anionic framework. The roles of the ionic liquid in ionothermal synthesis and crystallization of I are briefly discussed. (C) 2013 Elsevier B.V. All rights reserved.