Syntheses and crystal structures of the new zinc phosphonates Zn(O3PCH2P)(O)(R)(C6H5))center dot xH(2)O, based on mixed phosphonic acid phosphine oxide building blocks

The two new zinc(II) phosphonates Zn(O3PCH2P(O)(C6H5)(2)) (monoclinic P2(1)/c (No. 14), a = 9.961(2) Angstrom, b = 5.838(1) Angstrom, c = 24.608(5) Angstrom, beta = 101.48(3)degrees, Z = 4) and Zn(O3PCH2P(O)(CH3)(C6H5)). 0.67H(2)O (monoclinic P2(1)/c (No. 14), a = 15.879(5) Angstrom, b = 7.383(2) Angstrom, c = 10.475(3) Angstrom, beta = 105.01(5)degrees, Z = 4) were prepared by reaction of zinc nitrate, (R)(C6H5)P(O)CH2PO3H2 [R = C6H5, CH3], 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.