Zhen-Zhen Bao

Template synthesis and photochromism of a layered zinc diphosphonate

A zinc diphosphonate with protonated 2,4,6-tri(4-pyridyl)-1,3,5-triazine (H3TPT) as the template was hydrothermally prepared. The host layered framework was composed of 1-hydroxyethylidenediphosphonate and zinc ions. The guest H3TPT locates between the adjacent layers, acting as the charge balancer and template. The title compound features rapid photochromism upon irradiation with sunlight or UV light at ambient temperature.

An open-framework beryllium phosphite with extra-large 18-ring channels

A novel open-framework beryllium phosphite, [H4tren][Be6(HPO3)8]·(H2O)3 (1, tren = tris(2-aminoethyl)amine), was synthesized under solvothermal conditions. Its structure features a 3D interrupted network with a low density (1.594 g cm−3), and 1 represents the first example of a beryllium phosphite material with extra-large 18-ring channels.

Concise template syntheses of gallium phosphates driven by in situ direct alkylation of aliphatic and aromatic precursors by methanol

A family of open-framework gallium phosphates (GaPOs), namely [dmdabco]0.5[Ga(HPO4)2] (1, dmdabco = N,N′-dimethyl-1,4-diazabicyclo[2,2,2]octane), [tmpip]0.5[Ga3(OH)(PO4)3]·(H2O)0.25 (2, tmpip = N,N,N′,N′-tetramethyl-piperazinium), [mpy][Ga3F(PO4)3]·(H2O)0.25 (3, mpy = N-methyl-pyridine), [dmbpy]0.5[Ga2(HPO4)2(PO4)] (4, dmbpy = N,N′-dimethyl-4,4′-bipyridine), and [Hmpip]2[Ga7(OH)(PO4)6(HPO4)2] (5, mpip = N-methylpiperazine) have been fabricated under hydro(solvo)thermal conditions and structurally characterized. The in situ-template-synthesis strategy is firstly used to construct the gallium phosphates. The in situ generated dmdabco2+, tmpip2+, mpy+ and dmbpy2+ templates were derived from the methylation of two distinct types of organic-amine precursors under methanol media: aliphatic 1,4-diazabicyclo[2,2,2]octane (dabco) in 1, 1,4-dimethylpiperazine or 1-methylpiperazine or piperazine (pip) in 2, and aromatic pyridine (py) in 3 and 4,4′-bipyridine (bpy) in 4. Such a unique in situ methylation feature is different from classic Eschweiler–Clarke methylation in which excessive formic acid and formaldehyde is needed. Compound 1 exhibits infinite inorganic chains connected by hydrogen bonds to generate a 3D supramolecular framework; compounds 2 and 3 are isomorphous and constructed from a Ga6P6 secondary building unit (SBUs), forming a 3D pcu architecture with intersecting 8-membered channels; compound 4 possesses an inorganic layered structure and compound 5 features an interesting 3D open-framework architecture with helical channels.

Syntheses and Characterizations of Three Organically Templated Zinc Phosphites with 12-Ring Channels

Three new zinc phosphites, [Hapy]2[Zn3(HPO3)4] (1; apy = 4-aminopyridine), [H2hepip][Zn3(HPO3)4]·(H2O)0.25 (2; hepip = N-(2-hydroxyethyl)piperazine), and [H2tmdab][Zn3(HPO3)4] (3; tmdab = N,N,N′,N′-tetramethyl-1,3-diaminobutane), have been synthesized and characterized by infrared spectroscopy, elemental analysis, thermogravimetric analysis, and powder and single-crystal X-ray diffraction. The frameworks of 1–3 are constructed from 4-connected ZnO4 tetrahedra and 3-connected HPO3 pseudo pyramids with distinct connection mode driven by different organic amine templates. There are 12-membered ring (12-MR) and 8-MR apertures in the (3,4)-connected three-dimensional architecture of 1–3. It is notable that helical chains are observed in the framework of compound 3.

Synthesis, Structure, and Characterisation of Two New Open-Framework Zinc Phosphites of Varying Dimensionality

Using homopiperazine (hpip) as a structure directing agent, two new zinc phosphites [H2hpip][Zn2(HPO3)3] (1) and [H2hpip][Zn3(HPO3)4] (2), have been synthesised and structurally characterised by IR spectroscopy, elemental analysis, thermogravimetric analysis, and powder and single-crystal X-ray diffractions. Although both compounds are constructed from the same ZnO4 and HPO3 building units, the final frameworks are distinctly different due to their different connectivity. Compound 1 displays a 2D layered structure with 8-membered ring apertures, while compound 2 possesses a (3,4)-connected 3D architecture with multidirectional intersecting 8- and 12-ring channels. In addition, the simultaneous occurrence of four types of 8-ring channels intersecting the large 12-ring apertures in 2 is unique and observed here for the first time.

The inorganic–organic hybrid zinc phosphite poly[(μ3-hydrogen phosphito-κ3O:O′:O′′)(piperidin-1-ium-4-carboxylate-κO)zinc(II)]

A new inorganic-organic hybrid zinc phosphite, [Zn(HPO3)(C6H11NO2)]n, has been synthesized hydrothermally. Protonated piperidin-1-ium-4-carboxylate (PDCA) was generated in situ by hydrolysis of the piperidine-4-carboxamide precursor. The P atom possesses a typical PO3H pseudo-pyramidal geometry. The crystal structure features an unusual (3,4)-connected two-dimensional inorganic zinc-phosphite layer, with organic PDCA ligands appended to the sheets and protruding into the interlayer region. Helical chains of opposite chirality are involved in the construction of a puckered sheet structure.