Abstract: A new three-dimensional open-framework aluminophosphate [Al4P5O19(OH)]?[C6H18N2](AlPO-MPMD) and a new three-dimensional open-framework gallophosphate [Ga8P8O32F5.5]?[C6H18N2]2?[H3O+]1.5 (GaPO-MPMD) were hydrothermally synthesized with 2-methyl-1,5- pentamethylene diamine (MPMD) as structure directing agent. The compounds were characterized by single crystal and powder X-ray diffraction (XRD) analyses, TGA-DTA, solid MAS NMR analysis, optical rotation analysis, experimental and simulated vibrational circular dichroism (VCD) analysis. The results confirmed that S type of enantiomer of MPMD is preferredly included in the resulting open-framework of AlPO-MPMD and GaPO-MPMD. The in situ enantiomer (chiral) separation of organic structure directing agent under hydrothermal synthesis is achieved.