A novel Ag3L2 coordination cage derived from a tripodal oxazoline ligand: synthesis, structure and catalysis

Abstract

Coordination cages have attracted considerable attention recently due to the well-defined cavities and varied potential applications in different fields. In this work, a new tripodal oxazoline-based ligand with C3 symmetry, tris(4-(4,5-dihydrooxazol-2-yl)phenyl)amine (TOPA), was synthesized and employed to constitute coordination cage compounds. By the reaction of TOPA and AgPF6 at room temperature, a novel M3L2-type crystalline coordination cage complex was obtained with the formula of {[Ag3(TOPA)2]·(PF6)3}(1). In this complex, the adjacent two ligands coordinated with three Ag+ ions to form a coordination cage and these cages further generate the three-dimensional (3D) supramolecular networks through noncovalent interactions including hydrogen bond, C-H…π and F…Ag interactions. Moreover, cage complex 1 exhibited good catalytic performance in the cyclopropanation of styrene with methyl 2-diazo-2-(4-methoxyphenyl)acetate.