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A photochemical C-N coupling of aryl halides with nitroarenes is demonstrated for the first time. Catalyzed by a Ni II complex in the absence of any external photosensitizer, readily available nitroarenes undergo coupling with a variety of aryl halides, providing a step-economic extension to the widely used Buchwald-Hartwig C-N coupling reaction. The method tolerates coupling partners with steric-congestion and functional groups sensitive to bases and nucleophiles. Mechanistic studies suggest that the reaction proceeds via the addition of an aryl radical, generated from a Ni I /Ni III cycle, to a nitrosoarene intermediate. Scheme 1. Methods for the formation of aryl CÀN bonds.

Nowadays, although research of proton conductive materials has been extended from traditional sulfonated polymers to novel crystalline solid materials such as MOFs, COFs, and HOFs, research on crystalline ferrocene-based carboxylate materials is very limited. Herein, we selected two hydrogen-bonded and π–π interactions-supported ferrocenyl carboxylate frameworks (FCFs), [FcCO­(CH2)2COOH] (FCF 1) and [FcCOOH] (FCF 2) (Fc = (η5-C5H5)­Fe­(η5-C5H4)) to fully investigate their water-mediated proton conduction. Their excellent thermal, water, and chemical stabilities were confirmed by the means of thermogravimetric analyses, PXRD, and SEM determinations. The two FCFs indicate temperature- and humidity-dependent proton conductive features. Intriguingly, their ultrahigh proton conductivities are 1.17 × 10–1 and 1.01 × 10–2 S/cm, respectively, under 100 °C and 98% RH, which not only are comparable to the commercial Nafion membranes but also rank among the highest performing MOFs, HOFs, and COFs ever described. On the basis of the structural analysis, calculated E a value, H2O vapor adsorption, PXRD, and SEM measurements, reasonable conduction mechanisms are highlighted. Our research provides a novel inspiration for finding new high proton conducting crystalline solid materials. Importantly, the outstanding conducting performance of 1 and 2 suggests their, hopefully, potential in fuel cells and related electrochemical fields.

A highly effective hydroxylation reaction of aryl halides with water under synergistic organophotoredox and nickel catalysis is reported. The OH group of the resulting phenols originates from water, following deprotonation facilitated by an intramolecular base group on the ligand. Significantly, aryl bromides as well as less reactive aryl chlorides served as effective substrates to afford phenols with a wide range of functional groups. Without the need for a strong inorganic base or an expensive noble-metal catalyst, this process can be applied to the efficient preparation of diverse phenols and enables the hydroxylation of multifunctional pharmaceutically relevant aryl halides.

Two novel dimethylphenyl imidazole dicarboxylate-based lanthanide(III)-organic frameworks, [Ln(H2DMPhIDC)3(H3DMPhIDC)]n (Ln = Eu (1), Tb (2); H3DMPhIDC = 2-(3,4-dimethylphenyl)-1H-imidazole-4,5-dicarboxylic acid) have been synthesized under hydrothermal conditions. Single crystal X-ray diffraction analyses revealed that polymers 1 and 2 crystallize in the tetragonal space group I4₁ and exhibit isostructural three-dimensional (3D) solid-state frameworks. Both complexes indicate characteristic sharp emission bands of Eu(3+) or Tb(3+) ions, which are selectively sensitive to benzaldehyde-based derivatives (benzaldehyde, m-methylbenzaldehydes, m-carboxylbenzaldehyde and m-hydroxybenzaldehyde). These properties make both complexes potential fluorescence sensors for these chemicals.