Ionothermal Synthesis and Phase Transformation of Organic-inorganic Hybrid Neutral Zincophosphate Cluster [Zn(HPO4)(H2PO4)][C6H10N3O2]

Ionothermal synthesis was used to prepare a novel amino acid containing hybrid zincophosphate monomer,[Zn(HPO4)(H2PO4)][C6H10N3O2](denoted as ZnPO-CJ58).The inorganic framework of [Zn(HPO4)(H2PO4)]·[C6H10N3O2] consists of 4-membered rings formed by ZnO3OHis and PO2(OH)2 tetrahedra.The HPO4 and amino acid moieties hang on the Zn center.Such a framework is stabilized by extensive multipoint hydrogen bonds involving the phosphate units and histidine molecules to form a pseudo-3D supramolecular structure.It is noteworthy that ZnPO-CJ58 is the first zinc phosphate cluster with amino acid acting as the ligand.It exhibits photoluminescence excited at a wavelength of 220 nm.Interestingly,ZnPO-CJ58 can transform into a layered structure (C6H10N3O2)Zn2·(HPO4)(PO4)·H2O(ZnPO-CJ36) through further reacting with water or zinc acetate dihydrate in water at 85℃ for 1 h.This work will be helpful for the synthesis of crystalline inorganic-organic hybrid materials with biofunctional molecules.