Synthesis and Characterization of Copper(II)–Phosphonate Coordination Chain Array of Metallocages

Abstract

Reaction of CuCl2 ·2H2O and 2,4,6‐tris(phosphorylmethyl)mesitylene (H6tpmm) in H2O−DMF solution at room temperature afforded green crystals of [Cu6(H2tpmm)3(H2O)9]·3H2O (1), which were characterized by Fourier transform infrared (FT‐IR), thermogravimetric (TG) analysis, and powder X‐ray diffraction (PXRD). The solid‐state structure of 1 reveals a one‐dimensional chain array of M4L2 ‐metallocages constituted by the connection of two kinds of metallocage units, namely MC‐A (phosphonate/water‐bridged) and MC‐B (phosphonate‐bridged only), via μ2‐O(phosphonate)Cu bonds in ABAABA order. The tris‐phosphonate ligand H6tpmm is partially deprotonated to form H2tpmm4−, which displays a cis,cis,cis conformation to bridge six Cu(II) centers via two monodentate phosphonate groups in a η 0:η 0:η 1‐bonding mode and one tridentate phosphonate group in a μ4, η 1:η 1:η 2‐bondingng mode.