Two series of sandwich frameworks based on two different kinds of nanosized lanthanide(III) and copper(I) wheel cluster units

Chemistry. 2014 Mar 3;20(10):2704-11. doi: 10.1002/chem.201304165.

Abstract

Two series of sandwich frameworks, [La6(μ3-OH)2(ox)3L12Cu11(μ3-X)6(μ2-X)3]·8H2O (X=Br/Cl, FJ-21 a/b; L=4-pyridin-4-yl-benzonate; ox=oxalate) and [Ln4(OAc)3-(H2O)4L9][Cu(μ3-I)]@[Cu10(μ3-I)(μ4-I)6(μ5-I)3]·7H2O (Ln=Pr/Nd/Sm/Eu, FJ-22 a/b/c/d; OAc=acetate) have been hydrothermally prepared. These sandwich frameworks are assembled by two different kinds of nanosized lanthanide-(III) and copper(I) wheel cluster units, La18 and 3Cu@Cu24 in FJ-21, Ln24 and Cu2@Cu24 in FJ-22. The synergistic coordination between organic ligands, L and oxalate/acetate, leads to the formation of La18 and Ln24 wheels, while the synergistic coordination between organic L and inorganic Br/I ligands results in 3Cu@Cu24 and Cu2@Cu24 wheels for FJ-21 and FJ-22, respectively. Thus, two types of synergistic coordination between two different organic ligands, as well as inorganic and organic ligands are simultaneously observed in FJ-21 and FJ-22.