Syntheses and Crystal Structures of the New Zinc Phosphonates Zn(O3PCH2P(O)(R)(C6H5))·xH2O, Based on Mixed Phosphonic Acid−Phosphine Oxide Building Blocks

The two new zinc(II) phosphonates Zn(O(3)PCH(2)P(O)(C(6)H(5))(2)) (monoclinic P2(1)/c (No. 14), a = 9.961(2) Å, b = 5.838(1) Å, c = 24.608(5) Å, beta = 101.48(3) degrees, Z = 4) and Zn(O(3)PCH(2)P(O)(CH(3))(C(6)H(5))).0.67H(2)O (monoclinic P2(1)/c (No. 14), a = 15.879(5) Å, b = 7.383(2) Å, c = 10.475(3) Å, beta = 105.01(5) degrees, Z = 4) were prepared by reaction of zinc nitrate, (R)(C(6)H(5))P(O)CH(2)PO(3)H(2) [R = C(6)H(5), CH(3)], and sodium hydroxide in water in an autoclave. For the first compound, a unidimensional arrangement is observed, while for the second, a layered structure is obtained, in relation to the size of the substituents present on the phosphine oxide moiety.