An unexpected imidazole-induced porphyrinylphosphonate-based MOF-to-HOF structural transformation leading to the enhancement of proton conductivity.

Post-synthetic modification of proton-conducting metal-organic frameworks (MOFs) by loading small molecules capable of generating protons into pores is an efficient approach for developing a new type of material with improved ionic conductivity. Herein, the synthesis, characterization and proton conductivity of a novel electroneutral MOF based on palladium(II) -tetrakis(4-(phosphonatophenyl))porphyrinate, IPCE-1Pd, are reported. The exposure of the obtained framework to imidazole by the diffusion vapor method has surprisingly led to its complete crystal-to-crystal MOF-to-HOF transformation, resulting in the formation of a novel hydrogen-bonded organic framework (HOF) IPCE-1Pd_Im, which is the first example of such kind of structural change among all known MOFs.

Photochemistry of 2-(2-formylphenyloxy)acetic acid derivatives: synthesis of hydroxychromanones and benzofuranones.

Photochemical transformations of small molecules, such as -substituted benzaldehydes, in the absence of a photocatalyst are significantly underexplored and may reveal unexpected outcomes. In the present paper, we showed that 2-(2-formylphenoxy)acetic acid and its esters undergo photocyclization into chromanone and benzofuranone derivatives under 365 nm irradiation. The reaction occurs exclusively in dimethyl sulfoxide and can be used to efficiently obtain hydroxychromanones in good yields (27-91%).

Merging Johnson-Claisen and Aromatic Claisen [3,3]-Sigmatropic Rearrangements: Ytterbium Triflate/2,6-Di--butylpyridine Catalytic System.

General synthetic approach toward phenols with a polyfunctional side-chain is described. It is based on two subsequent [3,3]-sigmatropic rearrangements, in particular, Johnson-Claisen and aromatic Claisen. Facilitation of the reaction sequence is achieved by the separation of steps and discovery of the efficient catalysts for aromatic Claisen rearrangement.

An anionic porphyrinylphosphonate-based hydrogen-bonded organic framework: optimization of proton conductivity through the exchange of counterions.

Hydrogen-bonded organic frameworks (HOFs) possessing high crystallinity, simple synthetic procedure and easy regeneration provide high efficiency as multifunctional systems, including applications as proton conductors. Porphyrinylphosphonates having acidic moieties, which can form multiple hydrogen bonds, together with tunable physical-chemical properties of a macrocycle may significantly improve the proton conductivity of such materials. Herein, the synthesis, characterization and proton-conducting properties of a novel anionic HOF based on a new complex of palladium(II) with -tetrakis(4-(phosphonatophenyl))porphyrin, HOF-IPCE-1Pd, are reported.

Proton conductivity as a function of the metal center in porphyrinylphosphonate-based MOFs.

The rational design of metal-organic frameworks (MOFs) is highly important for the development of new proton conductors. Porphyrinylphosphonate-based MOFs, providing the directed tuning of physical and chemical properties of materials through the modification of a macrocycle, are potentially high-conducting systems. In this work the synthesis and characterization of novel anionic Zn-containing MOF based on palladium(ii) meso-tetrakis(3-(phosphonatophenyl))porphyrinate, IPCE-2Pd, are reported.