A metalloporphyrin-based porous organic polymer as an efficient catalyst for the catalytic oxidation of olefins and arylalkanes.

A metalloporphyrin-based porous organic polymer, Mn-PPOP-1, was constructed in high yield via the ketoenamine condensation of robust porphyrin tetraamines (TBPP) with 1,3,5-triformylphloroglucinol. The stable keto-enamine form in the synthesized polymer was unambiguously confirmed by 13C CP-MAS solid state NMR. Noticeably, besides the high thermal and chemical stability, this material contains both micropores and mesopores, which are favorable for mass transfer in the catalytic application. Mn-PPOP-1 exhibits significantly high catalytic oxidation of olefins and arylalkanes at room temperature. The catalytic activity and stability of Mn-PPOP-1 are apparently superior to those of the homogeneous manganese porphyrins. These results indicate that the metalloporphyrin-based porous organic polymer is a promising candidate for efficient heterogeneous catalysts.

A Hexagonal Covalent Porphyrin Framework as an Efficient Support for Gold Nanoparticles toward Catalytic Reduction of 4-Nitrophenol.

A hexagonal porphyrin-based porous organic polymer, namely, CPF-1, was constructed by 3+2 ketoenamine condensation of the C2 -symmetric porphyrin diamine 5,15-bis(4-aminophenyl)-10,20-diphenylporphyrin and 1,3,5-triformylphloroglucinol. This material exhibits permanent porosity and excellent thermal and chemical stability. CPF-1 can be employed as a superior supporting substrate to immobilize Au nanoparticles (NPs) as a result of the strong interactions between Au NPs and the CPF support. An Au@CPF-1 hybrid was synthesized by an interfacial solution infiltration method with NaBH4 as reducing agent. Au NPs (5 nm) grew on CPF-1 and were distributed without aggregation. Moreover, Au@CPF-1 exhibits superior catalytic activity compared to many other reported Au-based catalysts for the reduction of 4-nitrophenol in the presence of NaBH4 . In addition, Au@CPF-1 has excellent stability and recyclability, and it can be reused for three successive reaction cycles without loss of activity. The dense distribution of phenyl rings on the channel walls of the CPF support can reasonably be regarded as the active sites that adsorb the 4-nitrophenol molecule through hydrogen-bonding and C-H⋅⋅⋅π interactions, as was confirmed by the X-ray structure of model compound DAPP-Benz.

Enantiomers of tetrahedral metal-organic cages: a new class of highly efficient G-quadruplex ligands with potential anticancer activities.

Four pairs of enantiomers of water-stable tetrahedral metal-organic cages [Ni4L6](8+) were facilely synthesized. They efficiently stabilized antiparallel G-quadruplex DNA with moderate enantioselectivity, and displayed promising cytotoxicity against the human cancer cell lines HCT116, HepG2 and MCF-7. These results provide a new insight into the rational design of chiral G-quadruplex-based anticancer agents.

Iron(ii)-triazole core-shell nanocomposites: toward multistep spin crossover materials.

The first SCO@SCO core-shell nanomaterials have been synthesized by the step-by-step microemulsion method. The observed gyroscopic core-shell nanocomposites exhibit three-step spin crossover behaviour with thermal hysteresis at around room temperature. This offers an efficient and novel strategy for the development of multistable SCO materials.