TY - JOUR
T1 - Reactions of ZrOCl2 · 8H2O with carboxylic acids and thionyl chloride
T2 - Crystal and molecular structures of K4[Zr(mal)4] · 2H2O and K4[Zr(dipic)3]2 · 13.5H2O
AU - Willey, Gerald R.
AU - Woodman, Timothy J.
AU - Fisher, Michael
AU - Drew, Michael G.B.
PY - 1998/8/31
Y1 - 1998/8/31
N2 - Reactions of ZrOCl2 · 8H2O in aqueous solution with a carboxylic acid in the presence of K2CO3 have been studied as a route to ZrIV-carboxylates. With malonic acid (HO2CCH2CO2H) (H2mal) the product has been identified as K4[Zr(mal)4] · 2H2O (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) Å. 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) (H2dipic) the product has been characterised as K4[Zr(dipic)3]2 · 13.5H2O (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) Å; Zr - N, 2.343(8)-2.361(7) Å. The potassium cations show similar environments to those observed in structure (1). Dehydration of ZrOCl2 · 8H2O 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%).
AB - Reactions of ZrOCl2 · 8H2O in aqueous solution with a carboxylic acid in the presence of K2CO3 have been studied as a route to ZrIV-carboxylates. With malonic acid (HO2CCH2CO2H) (H2mal) the product has been identified as K4[Zr(mal)4] · 2H2O (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) Å. 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) (H2dipic) the product has been characterised as K4[Zr(dipic)3]2 · 13.5H2O (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) Å; Zr - N, 2.343(8)-2.361(7) Å. The potassium cations show similar environments to those observed in structure (1). Dehydration of ZrOCl2 · 8H2O 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%).
UR - http://www.scopus.com/inward/record.url?scp=33847244024&partnerID=8YFLogxK
U2 - 10.1023/A:1006933807192
DO - 10.1023/A:1006933807192
M3 - Article
AN - SCOPUS:33847244024
SN - 0340-4285
VL - 23
SP - 467
EP - 471
JO - Transition Metal Chemistry
JF - Transition Metal Chemistry
IS - 4
ER -