Synthesis, structure and characterization of two new organic template-directed gallium phosphate/phosphite-oxalates

Two new gallium phosphate/phosphite-oxalates hybrid solids, {[H₂dmpip][Ga₂(HPO₄)₂(PO₄)(C₂O₄)_0.5]·H₂O} (1) and [H₂apm][Ga₂(H₂PO₃)₂(HPO₃)₂(C₂O₄)] (2), where dmpip = 2,6-dimethyl-piperazine and apm = N-(3-aminopropyl)morpholine, have been synthesized and structurally characterized. Both of compounds 1 and 2 are formed by the connectivity of the Ga-based polyhedral, phosphite/phosphate groups as well as oxalate units. Compound 1 possesses a two-dimensional layer structure, in which the C₂O₄ units via an in-plane linkage connect two Ga center within the sheet. While in 2, the C₂O₄ units serve as bis-bidentates ligands bridging two GaO₆ octahedra from two distinct gallium-phosphite chains to give rise to inorganic-organic hybrid layer with 8-membered rings. In these materials, the structure-directing amines reside in the interlayer region and interact with the layers by way of hydrogen-bonds.