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

Reaction of CuCl 2 · 2H 2 O and 2,4,6‐tris(phosphorylmethyl)mesitylene (H 6 tpmm) in H 2 O − DMF solution at room temperature afforded green crystals of [Cu 6 (H 2 tpmm) 3 ( H 2 O ) 9 ]· 3H 2 O ( 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 M 4 L 2 ‐metallocages constituted by the connection of two kinds of metallocage units, namely MC ‐A (phosphonate/water‐bridged) and MC ‐B (phosphonate‐bridged only), via μ 2 ‐O(phosphonate)Cu bonds in ABAABA order. The tris‐phosphonate ligand H 6 tpmm is partially deprotonated to form H 2 tpmm 4− , 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 μ 4 ,  η 1 : η 1 : η 2 ‐bondingng mode.