Molecular di- and tetra-nuclear zinc(II) phosphates with sterically hindered aryl phosphate mono esters ligands

Abstract

Neutral dinuclear Zn(II) phosphates [Zn2(L)2(phen)2(H2O)2], (L = L2; (1)), anionic dinuclear Zn(II)-phosphates [Et3NH]+[Zn2(L1)4(pyz)2]− (2) and tetranuclear double-4-ring (D4R) Zn(II) phosphates [Zn4(L)4(DMF)4] (5–7), (L = L1; (3), L3; (4), L4; (5)), [Zn4(L1)4(pyz)2(DMF)2] (6) and [Zn4(L4)4(phen)2(DMF)2] (7) were synthesized by using the bulky aryl phosphate ligands (L = 2,6-(diphenylmethyl)-4-alkyl-phenyl substituted phosphates, ArOP(O)(OH)2 (Ar = 2,6-CHPh2-4-R-C6H2; R = Me (L1), Et (L2), i-Pr (L3), and t-Bu (L4)). The preparation of the complexes 1–7 was accomplished at room temperature by the use of additional co-ligands such as phenanthroline or pyrazole. Use of the linear co-ligand, 4,4′-bipyridine, affords the one-dimensional coordination polymer [Zn4(L3)4(bpy)(DMF)2]n, 8 which is built by the fusion of tetranuclear Zn(II) motifs. All the compounds were characterized by single crystal X-ray diffraction techniques.