METAL PHENOXYALKANOIC ACID INTERACTIONS .36. THE PREPARATION AND CRYSTAL-STRUCTURES OF TETRAAQUABIS(2-PHENOXYBENZOATO)NICKEL(II) DIHYDRATE, DIAQUABIS(4-FLUOROPHENOXYACETATO)ZINC(II), CATENA-DIAQUABIS(PHENOXYACETATO)COBALT(II) AND TETRAKIS-MU-[(PENTAFLUOROPHENOXY)ACETATO(O,O')]BIS[AQUACOPPER(II)]

The structures of four complexes involving divalent first-row transition metals and phenoxy substituted carboxylic acids have been determind by X-ray diffraction. These are tetraaquabis(2-phenoxybenzoato)nickel(II) dihydrate (1), diaquabis(4-fluoro-phenoxyacetato)zinc(II) (2), diaquabis(phenoxyacetato)cobalt(II) (3) and tetrakis-mu-(penta-fluorophenoxyacetato)bis[aquacopper(II)] (4). Complex 1 is regular octahedral with trans-related unidentate carboxylates [Ni-O (carboxylate) 2.03](1) angstrom] and four waters [Ni-O 2.049,2.104(2) angstrom]. Complex 2 has a skew trapezoidal bipyramidal stereochemistry, involving four oxygens from two asymmetric bidentate carboxylates [Zn-O 2.107, 2.332(3) angstrom] and two waters [Zn-O 1.989(4) angstrom]. The polymeric complex 3 is isomorphous and isostructural with the manganese(II) analogue, with centrosymmetric octahedral CoO6 stereochemistry comprising four bonds to carboxylate oxygens (both bridging) [Co-O 2.076, 2.087(3) angstrom] and two to waters [Co-O 2.134(3) angstrom]. Complex 4 is a pseudo-centrosymmetric tetra-carboxylate bridged dimer of the copper(II) acetate hydrate type with a Cu-Cu separation of 2.644(4) angstrom. Bond distances to copper are 1.96(1) (average, equatorial) and 2.15(1) angstrom (average, axial, to water).