Structures of bis-ethylmaltolatodichloro-tin(IV) and -titanium(IV) and of trichloro(1-methyl-2-ethyl-3-hydroxy-4H-pyridin-4-onato)-aquatin(IV)

The structures of solvates of the bis-ethylmaltolatodichloro-metal(Iv) complexes M(etma)(2)Cl-2 with M = Sn and Ti, and of trichloro(lmethyl-2-ethyi-3-hydroxy-4H-pyridin-4-on)aquatin(IV), Sn(mepp)Cl-3(H2O), have been established by single crystal X-ray diffraction methods. Sn(etma)(2)Cl-2, crystallised with one molecule of dichloromethane, Ti(etma)(2)Cl-2 with one molecule of tetrahydrofuran, and Sn(mepp) Cl-3(H2O) with one molecule of acetone, from their respective recrystallisation media. Both ethylmaltol complexes M(etma)(2)Cl-2 are cis-octahedral. The coordination around the tin atom in Sn(mepp) Cl-3(H2O) approximates to octahedral, with the three chloride ligands in fac geometry. The tin(IV)-water bond distance in this pyridinone complex is discussed in relation to this distance in other aquatin(IV) complexes. The effects of coordinating tin(IV) on the geometry of the coordinated pyridinone are considered. (C) 2000 Elsevier Science Ltd All rights reserved.