Metal ion dominated ligand conformation variations on phosphonate bridged dinuclear complexes

摘要

Graphical abstract Display Omitted Highlights ? Phosphonate bridged metal ions with 2,2′-bipyridine to form dinuclear complexes. ? Metal ions dominated tris-phosphonate to generate two different conformations. ? Complexes showed two different structures influenced by ligand conformations. Abstract Reactions of 2,4,6-tris(phosphorylmethyl)mesitylene (H6tpmm), 2,2′-bipyridine, and CuCl2·2H2O and MCl2·6H2O (M =Ni, Co) in H2O–MeOH solution at 80°C afforded related dinuclear metal–phosphonate complexes [Cu2(H4tpmm)2(2,2′-bipyridine)2(H2O)2]·H2O (1) and [M2(H4tpmm)2(2,2′-bipyridine)2(H2O)4] (M=Ni, 2; Co, 3). The partially deprotonated H4tpmm2? ligand displays a cis,trans,trans conformation with a η 2:η 0:η 0-bonding mode in 1 and a cis,cis,cis conformation with a η 1:η 1:η 0-bonding mode in 2 and 3. Such variations in ligand conformation and coordination mode in the Cu(II), Ni(II), and Co(II) complexes might be attributed to preferences of metal coordination, which significantl