New Inorganic−Organic Hybrid: Synthesis and Structural Characterization of an Alumino(oxalato)phosphate

A new 3-D alumino(oxalato)phosphate, [H3NCH(CH3)CH2NH3]2[Al4P6O20(OH)4(C2O4)(H2O)],
consists of aluminophosphate layers which are pillared by oxalate anions. It contains a hybrid
12-membered channel where guest species, diprotonated 1,2-diaminopropane and water
molecules, are found. The layers are composed of AlO6, AlO4, and PO4 polyhedra giving double
chains, which are interconnected through Al−O−P−O−Al bridges. Oxalate ions are
quadridentately bonded by participating in the coordination of AlO6 and by bridging the
aluminophosphate layers. The guest species strongly interact with the alumino(oxalato)phosphate layers which is evidenced by solid-state NMR spectroscopy. Crystal data are: 
triclinic, space group P1̄, a = 8.611(1) Å, b = 9.096(1) Å, c = 11.371(1) Å, α = 104.811(1)°,
β = 111.368(1)°, and γ = 94.248(1)°, V = 787.9(1) Å3, and R = 0.041.