The structures of bis-maltolato-zinc(II) and of bis-3-hydroxy-1,2-dimethyl-4-pyridinonato-zinc (II) and -lead(II)

The structures of bis-(3-hydroxy-4-pyronato)zinc(II) {bis-maltolato-zinc(II), Zn(malt)(2). 1.5H(2)O}, bis-( 1,2-dimethyl-3-hydroxy-4-pyridinonato)zinc(II) {Zn(L1)(2). 7H(2)O}, and bis-(1,2-dimethyl-3-hydroxy-4-pyridinonato)lead(II) {Pb(L2)(2). 7H(2)O}, determined by X-ray diffraction techniques, are reported. The zinc in {Zn(L1)(2). 7H(2)O} is five coordinated; in Zn(malt)(2). 1.5H(2)O zinc occurs in both five- and six-coordination. Pb(L1)(2). 7H(2)O is dimeric; each lead has five oxygens, two of them bridging, in its coordination shell. All three compounds contain water molecules coordinated to the metal; both L1 complexes also contain water of crystallisation in the form of extended chains. All three compounds are extensively hydrogen bonded. (C) 2000 Elsevier Science Ltd All rights reserved.