Synthesis and characterization of three-layered zinc phosphites containing tert-octylamine molecules with template and ligand roles

Three-layered zinc phosphites containing single monoamine molecules with different roles have been synthesized using hydro(solvo)thermal methods and characterized by single-crystal X-ray diffraction, thermogravimetric analysis, and infrared spectroscopy. Compound 1, (C8H17NH3)4Zn3(HPO3)5·3H2O, consists of 20-ring layer structures sandwiched by water molecules and protonated tert-octylamine molecules. The structure of Zn(C8H17NH2)(HPO3) (compound 2) is composed of 4.82 network structures, wherein the tert-octylamines are coordinated to the Zn atom as pendant groups. Compound 3, (C8H17NH3)2Zn4(C8H17NH2)(HPO3)5, was prepared in which the amine plays a dual role as both a ligand and a countercation. In addition, compound 1 is the first layered metal phosphite with large 20-ring windows. This group of substances represents the first example of the preparation of compounds in which the reactivity of incorporated single amine molecules is varied by adjusting the synthesis conditions. - Graphical abstract: The first layered metal phosphite with large 20-ring windows, (C8H17NH3)4Zn3(HPO3)5·3H2O (1), sandwiched by water molecules and protonated tert-octylamine molecules. Highlights: • The first example of zinc phosphites contains amine molecules with template and ligand roles. • The reactivity of single amine molecules is varied by adjusting the synthesis conditions. • Compound 1 contains the largest pore opening of 20-rings in known layered metal phosphites. • Compound 3 has dual roles of amine molecules in its structure