| Abstract: | A novel crystalline zinc diphosphonate, (CH3NH3 )4Zn2 (xbp)2•H2O , denoted as compound 1 , was ionothermally synthesized from tetraethyl‐p ‐xylylenebisphosphonate (Texbp) and Zn(OAc )2 in a protic eutectic mixture with urea/methylamine hydrochloride. Its structure was determined by single‐crystal X‐ray diffraction data and had a special three‐dimensional open framework with rhombic channels. Compound 1 belongs to the monoclinic system (space group C2 /c ), with lattice parameters a =22.6876(19) Å, b =8.73 76(7) Å, c =8.1673(9) Å, β =108.146(2)°, V =1538.5(2) Å3, Z =2. Its structure is totally different from the typical organic pillared structure, only two oxygens of the phosphonate group are coordinated with zinc atoms, and the third oxygen exists in the terminal form, which is similar to the popular dicarboxylate linkers in MOFs . The organic cations CH3NH3 ]+ of the eutectic mixture played a structure‐directing role for constructing this framework and were confined in the pore channels to balance the negative charges resulting from the zinc phosphonate inorganic chains. |
