Reactions of ZrOCl2 center dot 8H(2)O with carboxylic acids and thionyl chloride: crystal and molecular structures of K-4[Zr(mal)(4)]center dot 2H(2)O and K-4[Zr(dipic)(3)](2)center dot 13.5H(2)O
UNSPECIFIED. (1998) Reactions of ZrOCl2 center dot 8H(2)O with carboxylic acids and thionyl chloride: crystal and molecular structures of K-4[Zr(mal)(4)]center dot 2H(2)O and K-4[Zr(dipic)(3)](2)center dot 13.5H(2)O. TRANSITION METAL CHEMISTRY, 23 (4). pp. 467-471. ISSN 0340-4285Full text not available from this repository.
Reactions of ZrOCl2. 8H(2)O in aqueous solution with a carboxylic acid in the presence of K2CO3 have been studied as a route to Zr-IV-carboxylates. With malonic acid (HO2CCH2CO2H) (H(2)mal) the product has been identified as K-4[Zr(mal)(4)]. 2H(2)O (1) by X-ray crystallography. The individual eight-coordinate zirconium anions contain four bidentate (OO') malonate anions with the metal geometry approximating to a square antiprism with each chelating ligand spanning the two square faces, Zr-O 2.091(3)-2.288(3) Angstrom. The four potassium cations feature irregular coordination spheres of oxygen atoms [from both H2O and (mal) ligand molecules] with a 7-9 coordination range. With 2,6-dicarboxypicolinic acid (HO2CC5NH3CO2H) (H(2)dipic) the product has been characterised as K-4[Zr(dipic)(3)](2). 13.5H(2)O (2) following X-ray diffraction studies. The structure consists of two [Zr(dipic)(3)](2-) anions, four potassium cations and lattice solvate (H2O) molecules. Individual anions feature nine-coordinate zirconium in which each dipic ligand is terdentate, being bonded via one N (pyridine) and two O (carboxylate) atoms. The metal geometry approximates to tricapped trigonal prismatic with each nitrogen atom capping a regular face of four oxygen atoms, Zr-O, 2.216(6)-2.261(6) Angstrom; Zr-N, 2.343(8)-2.361(7) Angstrom. The potassium cations show similar environments to those observed in structure (1). Dehydration of ZrOCl2. 8H(2)O using SOCl2 in the presence of an excess of THF effects removal of coordinated H2O molecules and hydroxy bridging groups to provide the anhydrous bis-adduct ZrCl4(thf)(2) in good yield (72%).
|Item Type:||Journal Article|
|Subjects:||Q Science > QD Chemistry|
|Journal or Publication Title:||TRANSITION METAL CHEMISTRY|
|Publisher:||KLUWER ACADEMIC PUBL|
|Number of Pages:||5|
|Page Range:||pp. 467-471|
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