文摘
In this work, a series of new metal phosphonates were hydrothermally synthesized and structurally characterized based on m-xylylenediphosphonic acids (H4L), including [M(H2L)(bpy)] (M?=?Mn 1, Co 2), [MH2L)(phen)] (M?=?Co 3, Cu 4), and [Cu2(H2L)2(bpy-2] 5 (bpy?=?2,2-bipyridine, phen?=?1,10-phenanthroline, bpy″??4,4-dimethyl-2,2-bipyridine). X-ray diffraction indicated that compounds 1 and 2 were isomorphic. Complexes 3 and 4 were shown to crystallize in different space groups but had similar crystallographic units. In the complexes, H4L was seen to partially deprotonate to afford H2L2?/sup>. The H2L2?/sup> ligands in 1-strong class="a-plus-plus">4 functioned as tetradentate ligands with each phosphonate group adopting bidentate coordination mode with two M centers to generate a 2D layer. In addition, the H2L2?/sup> anions in 5 functioned as tridentate ligands with one phosphonate group adopting the bidentate mode and another phosphonate group adopti ng the monodentate mode, thus linking three Cu atoms to provide a 1D chain. The IR and thermal stabilities of these compounds were subsequently examined.