Synthesis and crystal structures of three zinc (chloromethyl)phosphonates Academic Article uri icon

abstract

  • Reaction of zinc compounds with (chloromethyl)phosphonic acid yielded three novel layered compounds. Zn(O3-PCH2Cl)·H2O was prepared from zinc acetate and the phosphonic acid at 70 °C. It is monoclinic, space group P21/n, with a = 4.781(2) Å, b = 19.816(8) Å, c = 5.6975(8) Å, β = 91.91(2)°, and Z = 4. This compound has a layered structure similar to that of Zn(O3PC6H5)·H2O.1 Addition of urea to the reaction mixture yielded another layered product in which urea is coordinated to zinc through oxygen. The compound is monoclinic, P21/c, with a = 5.040(3) Å, b = 8.522(3) Å, c = 17.401(2) Å, β = 89.80(2)°, and Z = 4. The zinc atom is tetrahedrally coordinated by three phosphonate oxygens and one from urea. The phosphonate oxygens bridge across two zinc atoms forming a chain of eight-membered rings running parallel to the a-axis. The chains are linked together through hydrogen bonding along the b-axis to form the layers. Zn2Cl(O3PCH2Cl)(HO3PCH2Cl)·3H2O was prepared at 60 °C from a mixture of ZnCl2 and (chloromethyl)phosphonic acid. The crystals are orthorhombic, Pbca, with a = 19.500(4) Å,b= 17.686(3) Å, c = 8.198(1) Å, and Z = 8. Zinc atoms are both tetrahedrally and octahedrally coordinated. The latter type of Zn atoms are joined in a cluster of two by bridging phosphonate oxygens forming four-membered rings. Each of these Zn atoms is bridged in the opposite direction by phosphonate groups to tetrahedrally coordinated Zn atoms. The octahedra are completed by three water molecules. A chlorine atom is bonded directly to the tetrahedral zinc. The phosphonate bridging of metal atoms forms 14-membered rings and 12-membered rings in addition to the 4-membered rings. Each of the interlayer distances are determined by the way in which the chloromethyl group is situated in the interlamellar space. © 1993, American Chemical Society. All rights reserved.

author list (cited authors)

  • Bhardwaj, C., Hu, H., & Clearfield, A.

citation count

  • 35

publication date

  • September 1993