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A metal-free and redox-neutral trifluoromethyl-hydrazination method of alkenes is described. With a commercially available photocatalyst and low-cost reagents, both conjugated and isolated alkenes could be converted to β-trifluoromethyl hydrazines in good to excellent yields. The versatile hydrazine group can be either used for heterocycle synthesis or cleaved to afford a corresponding amine. Mechanistic studies suggested this reaction goes through a radical addition cascade pathway, featuring a fast and irreversible trifluoromethylation and a relatively slow radical hydrazination step.A new methodology for the carbonylative transformation of N-fluoro-sulfonamides into N-sulfonyl-β-homoproline esters has been described. In the presence of a catalytic amount of Cu(OTf)2, a range of β-homoproline derivatives were prepared in moderate to good yield. The reaction proceeds via the intramolecular cyclization and intermolecular carbonylation of a free carbon radical. Notably, this procedure offers the possibility to build potential functionalized bioactive molecules.Surface deformation modes, such as wrinkling, creasing, and cracking, enable a plethora of surface morphologies under mechanical loading, which have been widely exploited to provide flexibility and stretchability to electronic devices. As each phenomenon offers a distinct set of potential advantages, controlling the types and spatial locations of deformation modes is key for their successful application. In this study, we demonstrate a method to simultaneously harness multiple surface deformation modes-wrinkles, creases, and cracks-in patterned multilayer films. The wrinkling of metal-coated stiff patterned films provides flexibility and stretchability, while the reversible formation of creases in the intervening regions of the bare elastomer is used to template the formation of patterned cracks in the metal. While conventional cracks can be difficult to precisely control, the patterned cracks demonstrated here remain straight over long distances and show tunable lateral spacings from hundreds of micrometers to centimeters. Finally, the reversible opening and closing of these cracks under mechanical loading provides mechanically gated electrical switches with small and tunable critical switching strains of 0.05-0.18 and high on/off ratios of &gt;107, enabling the preparation of mechanical NAND and NOR logic gates each composed of multiple patterned switches on a single elastomer surface.N-type silicon is a kind of semiconductor with a narrow band gap that has been reported as an outstanding light-harvesting material for photoelectrochemical (PEC) reactions. Decorating a thin catalyst layer on the n-type silicon surface can provide a direct and effective route toward PEC water oxidation. However, most of catalyst immobilization methods for reported n-type silicon photoanodes have been based on energetically demanding, time-consuming, and high-cost processes. Herein, a high-performance NiFeP alloy (NiFeP)-decorated n-type micro-pyramid silicon array (n-Si) photoanode (NiFeP/n-Si) was prepared by a fast and low-cost electroless deposition method for light-driven water oxidation reaction. The saturated photocurrent density of NiFeP/n-Si can reach up to ∼40 mA cm-2, and a photocurrent density of 15.5 mA cm-2 can be achieved at 1.23 VRHE under light illumination (100 mW cm-2, AM1.5 filter), which is one of the most promising silicon-based photoanodes to date. The kinetic studies showed that the NiFeP on the silicon photoanodes could significantly decrease the interfacial charge recombination between the n-type silicon surface and electrolyte.Diazenes are valuable compounds that have found broad applicability because of their optical and biological properties. We report the synthesis of alkylaryldiazenes via formal, photoredox-catalyzed, deformylative C-N bond formation. The procedure employs dihydropyridines for the generation of alkyl radicals, which are then trapped by diazonium salts and reduced to the corresponding diazenes. Control experiments were performed to confirm the involvement of radicals in the mechanism. [https://www.selleckchem.com/btk.html BTK inhibitor clinical trial] The reaction can be carried out at room temperature and employs readily available reagents; the mild conditions allowed the use of highly functionalized substrates. There was no observed tautomerization of the diazenes to the corresponding arylhydrazones.The boron-centered radicals derived from alkenyl N-heterocyclic carbene (NHC)-boranes bearing ester substituents were recently found to ring close in 5-endo mode by addition to the oxygen atoms of the ester substituents. The inference from this was that NHC-boryl radicals might add intermolecularly to carbonyl-containing substrates. Several different NHC-boryl radicals were generated by H-atom abstraction from NHC-ligated trihydroborates. Electron paramagnetic resonance (EPR) spectroscopy proved that these did indeed add to the oxygen atoms of diaryl ketones with production of the corresponding bora-ketyl radicals. The same unusual regioselectivity of addition was observed with monoaryl ketones, but no bora-ketyls were observed with dialkyl ketones. Similarly, no bora-ketyl adduct radicals were observed with esters, even esters of benzoic acid. EPR spectroscopic evidence suggested that NHC-boryl radicals were also added to the O-atoms of aromatic aldehydes. Amine-boryl and phosphine-boryl radicals were also observed to add to the O-atom of benzophenone with production of the corresponding ketyl radicals.Covalent organic frameworks (COFs) are a promising category of porous materials possessing extensive chemical tunability, high porosity, ordered arrangements at a molecular level, and considerable chemical stability. Despite these advantages, the application of COFs as membrane materials for gas separation is limited by their relatively large pore apertures (typically &gt;0.5 nm), which exceed the sieving requirements for most gases whose kinetic diameters are less than 0.4 nm. Herein, we report the fabrication of ultrathin two-dimensional (2D) membranes through layer-by-layer (LbL) assembly of two kinds of ionic covalent organic nanosheets (iCONs) with different pore sizes and opposite charges. Because of the staggered packing of iCONs with strong electrostatic interactions, the resultant membranes exhibit features of reduced aperture size, optimized stacking pattern, and compact dense structure without sacrificing thickness control, which are suitable for molecular sieving gas separation. One of the hybrid membranes, TpEBr@TpPa-SO3Na with a thickness of 41 nm, shows a H2 permeance of 2566 gas permeation units (GPUs) and a H2/CO2 separation factor of 22.