Abstract The development of visible‐light‐induced photocatalysts for chemoselective functional group transformations has received considerable attention. Polyoxometalates (POMs) are potential materials efficient because their properties can be precisely tuned by changing constituent elements and structures the introduction additional metal cations. Furthermore, they thermally oxidatively more stable than frequently utilized organometallic complexes. visible‐light‐responsive tetranuclear...

Given the interactive media characteristics and intrinsically motivating appeal, computer games are often praised for their potential value in education.allHowever, comprehensive research testing these assumptions is still missing. Preliminary comparative studies on learning effects of versus traditional have shown some promise. In this paper, we describe a study that thoroughly investigates interactivity richness science among college students. We also discuss important results implications...

An intermolecular 1,2-diacylation of alkenes is disclosed via cooperative N-heterocyclic carbene and photoredox catalysis under the mediation PPh3 Cs2CO3. This protocol provides a practical approach for construction 1,4-dicarbonyl compounds toward novel diketone pharmaceutical derivatives. Furthermore, regioselective dicarbonyl can be synthesized by adding acyl azolium salt. Mechanistic investigations suggest that process was critical radical/radical cross coupling ketyl radicals with...

Abstract The development of visible‐light‐induced photocatalysts for chemoselective functional group transformations has received considerable attention. Polyoxometalates (POMs) are potential materials efficient because their properties can be precisely tuned by changing constituent elements and structures the introduction additional metal cations. Furthermore, they thermally oxidatively more stable than frequently utilized organometallic complexes. visible‐light‐responsive tetranuclear...

We report a copper metallaphotocatalytic 1,2-difunctionalization of terminal alkynes with N-hydroxyphthalimide (NHP) esters and readily available silyl reagents (TMSCN TMSNCS) to access stereodefined trisubstituted alkenes, including (E)-alkenyl nitriles thiocyanates. The reaction proceeds excellent anti-stereoselectivity demonstrates broad compatibility wide range NHP as alkyl radical precursors. Experimental computational studies have been performed gain insight into the mechanism.

A cobaloxime-catalyzed photochemical synthesis of allyl monofluorides from styrenes is described herein. This method characterized by mild reaction conditions, low-cost catalyst, and broad substrate scope. Furthermore, this convenient will provide a facile toward novel monofluoroalkylated natural product pharmaceutical derivatives. Mechanistic investigations indicate that monofluoroalkyl radical involved in the catalytic cycle.

Abstract A tetranuclear cerium-containing polyoxometalate, TBA6[{Ce(H2O)}2{Ce(CH3CN)}2(µ4-O)(γ-SiW10O36)2] (I, TBA: tetra-n-butylammonium), showed a unique intramolecular multiple electron transfer (Ce3+-to-POM(W6+)) on irradiation of visible light (λ > 400 nm). This could induce hydrogen (H2) evolution using alcohols as the donors, and high turnover number (TON) 1960 was achieved. Moreover, I be reused without an appreciable loss in its catalytic performance.

The direct photocatalyzed para-selective CAr-H difluoroalkylation of aromatic aldehyde derivatives has been accomplished using a newly explored catalytic system. In addition, when para-substituted benzaldehydes as substrates, ortho-selective was also accomplished. It is worth noting that all the above site-selectivity opposite to traditional Friedel-Crafts reactions aldehydes. preliminary mechanistic investigations indicate an electrophilic difluoroalkyl radical involved in cycle.

An intermolecular direct α-C–H acylation of alkenes was revealed by the visible-light-mediated N-heterocyclic carbene and quinuclidine catalysis. This convenient protocol provides a facile synthesis toward novel natural products drug derivatives α-substituted vinyl ketones. Mechanistic investigations indicated that transformation proceeded via sequential radical addition, coupling, an elimination process.

The trisubstituted cyclohexenone 12, generated through a palladium-catalyzed Ullmann cross-coupling reaction between o-iodonitrobenzene and 4,5-trans-disubstituted 2-iodo-2-cyclohexen-1-one, engaged in tandem reductive cyclization process upon exposure to hydrogen gas the presence of Raney cobalt. As result, 1,5-methanoazocino[4,3-b]indole 13 was obtained this could be readily elaborated racemic modifications alkaloids uleine, dasycarpidone, noruleine, nordasycarpidone (1-4, respectively).

Monitoring subtle temperature changes noninvasively remains a challenge for magnetic resonance imaging (MRI). A temperature-sensitive contrast agent based on thermosensitive microgel is proposed and synthesized using manganese tetra(3-vinylphenyl) porphyrin core reacting with N-isopropylacrylamide (NIPAM) or N-isopropylmethacrylamide (NIPMAM) monomers N,N′-methylenebis(acrylamide) (MBA) cross-linkers. The volume of the NIPAM-incorporated (M-1) decreased sharply around its lower critical...

Abstract Series of magnetic Cu/Fe 3 O 4 nanoparticles (NPs) with different Cu loading were prepared by co‐precipitation method and studied as catalysts for the conversion furfural to cyclopentanone (CPO) or cyclopentanol (CPL), respectively in aqueous phase. It is found that product distribution was affected hydrogen pressure, reaction temperature, time active metals. X‐ray diffraction (XRD), photoelectron spectroscopy (XPS) Transmission electron microscope (TEM) used characterize catalysts....

Direct access to benzo-fused aza-macrolides was successfully achieved through iridium-catalysed intermolecular decarboxylative coupling of vinylethylene carbonates with isatoic anhydrides under relatively mild reaction conditions. Notably, this proceeded sequential allyl-amination/macrolactonization upon extrusion CO2. Moreover, favourable fluorescence properties could be observed in the title macrocyclic products.

Abstract A new zinc‐magnesium‐aluminum‐layered double hydroxide (ZnMgAl‐LDH) was prepared by one‐step coprecipitation using agents extracted from waste residue and intercalated with stearate anions. The X‐ray diffraction Fourier transform infrared spectra show that the anions have successfully into interlayer of ZnMgAl‐LDH. scanning electron microscopy shows typical sand‐rose morphology LDH. enhanced thermal stability confirmed Congo red test. poly(vinyl chloride) (PVC)/ZnMgAl‐LDH‐stearate...

A total synthesis of the title sesquiterpene 4 is described that starts with chiral, non-racemic cis-1,2-dihydrocatechol 10 obtained through whole-cell biotransformation p-iodotoluene. Compound elaborated over seven steps, including Negishi cross-coupling and intramolecular Diels–Alder (IMDA) cycloaddition reactions, to ketone 7 engages in a photochemically promoted 1,3-acyl migration so affording cyclobutanone 6. 6 was converted further steps into compound 4.

Herein, a three-component 1,2-thiosulfonylation of alkenes with thiophenols and sulfonyl chlorides via synergistic photoredox iron catalysis is described. Compared previous studies, this protocol avoids tedious pre-synthesis thiosulfonates employs more readily accessible as sulfonation reagent. Moreover, the reaction exhibits high compatibility styrenes unactivated well diverse chlorides, especially sulfamoyl chlorides. Preliminary mechanism investigations reveal that radical pathway...

Abstract A general, concise, four‐step synthetic sequence for the preparation of spirodiamine templates is described herein.

Reductive cyclization of the 2,4,5-trisubstituted cyclohexenone 16 using dihydogen in presence Raney cobalt afforded compound 17 (60%) that could be elaborated over a further five steps, including one involving cationic process, into racemic modification unusual uleine alkaloid gilbertine. Single-crystal X-ray analyses compounds (±)-1, 16, and derivative are reported.