Metal arsonate polymers of Cd, Zn, Ag and Pb supported by 4-aminophenylarsonic acid

The coordination preferences of 4-aminophenylarsonic acid, 4-NH2C6H4AsO3H2, (p-arsanilic acid) with CdCl2·2.5H2O, ZnCl2, Ag(SO3CF3) and Pb(NO3)2 have been investigated affording five new metal arsonate polymers. The reaction between 4-aminophenylarsonic acid and CdCl2·2.5H2O resulted in a one-dimensional polymer, [{Cd(4-NH3C6H4AsO3H)(Cl)2}(H2O)2]n, 1, in which the polymeric chain is propagated by bridging chlorides. Exchange of CdCl2 for ZnCl2 afforded [{Zn2(4-NH3C6H4AsO3)(Cl)2}(H2O)2(Cl)]n, 2, featuring interlinked 6- and 8-membered [Zn–O–As] ring systems. The reaction of Ag(SO3CF3) with 4-aminophenylarsonic acid, afforded polymeric 3, [Ag(4-NH2C6H4AsO3H)(4-NH2C6H4AsO3H2)]n where coordination of the amino group to the silver center is observed and [{Ag2(4-NH3C6H4AsO3H)(4-NH3C6H4AsO3)(μ2-SO3CF3)2}(SO3CF3)2]n, 4. By comparison, the reaction of p-arsanilic acid with Pb(NO3)2 yielded a polymeric chain [Pb(4-NH3C6H4AsO3H)(NO3)2]n, 5 of similar topology to 1. The structures of 1–5 have been indiscriminately characterized by single crystal X-ray diffraction and their composition supported by relevant spectroscopic techniques. A comparison of the structural features of these polymers is used to determine the coordination preference of the ligand and factors influencing structural motifs, for example, the role of the anion. The reaction of 4-aminophenylarsonic acid, 4-NH2C6H4AsO3H2, with cadmium, zinc, silver, and lead have resulted in five new metal arsonate polymers that have been characterized by single crystal X-ray diffraction and spectroscopic means. [Display omitted] ► The synthesis of five novel metal arsonates with 4-aminophenyl arsonic acid. ► Single crystal X-ray diffraction studies revealed polymeric structures. ► The luminescent properties of the metal arsonates were investigated.