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Two new europium coordination compounds, [Eu2(papip)2(PhCOO)6] and [Eu2(phpip)2(PhCOO)6] (papip is 1-phenyl-2-(4-aminophenyl)imidazo[4,5-f][1,10]phenanthroline and phpip 1-phenyl-2-(4-hydroxyphenyl)imidazo[4,5-f][1,10]phenanthroline), have been synthesized hydrothermally and structurally characterized, involving the in situ hydrolysis of phenylacetonitrile to phenylacetate. The –NH2 group in the former complex was unexpectedly generated from the –NO2 group of free 1-phenyl-2-(4-nitrophenyl)imidazo[4,5-f][1,10]phenanthroline during the reaction process, representing the first such transformation in a hydrothermal reaction. Both complexes exhibit bright red photoemission typical of Eu(III) f–f transition under UV excitation, with long excited state lifetimes and quite high photoluminescence quantum yields. [ABSTRACT FROM AUTHOR]

We presented a first example of cobalt-electro-catalyzed enantioselective C–H acyloxylation of arylphosphinamides with carboxylic acids, enabling the concise synthesis of oxygenated phosphamides featuring a P-stereogenic center. These compounds were synthesized with acceptable yields and outstanding enantioselectivities. The reaction demonstrated a broad substrate scope and good functional group tolerance. Additionally, the facile conversion of the acyloxy group to a free hydroxyl group provides opportunities for further chemical manipulations, underscoring the versatility of this strategy. [ABSTRACT FROM AUTHOR]

The first example of manganese-catalyzed asymmetric transfer hydrogenation of N-heteroaromatics in water is reported. This ATH reaction proceeds smoothly without the need for inert atmosphere protection in the presence of a water-stable manganese catalyst, which bears an easily available aminobenzimidazole ligand. Ammonia borane, regarded as a green, cheap and high atom economical hydrogen source, was applied. Various quinolines are transformed into the desired products in high yields and up to 99% enantiomeric excess (ee). The utility of the current protocol was demonstrated by applying it in the gram-scale total synthesis of the Hancock alkaloid (−)-cuspareine with 96% overall yield. [ABSTRACT FROM AUTHOR]

The development of an electrochemical process method for the synthesis of P-chiral phosphine derivatives poses a considerable challenge. Here, we present an electricity-driven cobalt-catalyzed enantioselective C–H annulation of arylphosphinic amides and alkynes, which provides rapid access to P-chiral cyclicphosphorus oxides in good yields with excellent enantioselectivities (48–99% yields, 94–>99% ee). The reaction was compatible with aqueous solvents and proceeded efficiently in a shorter reaction time compared with the previous work using oxidants. The process employs a combination of readily available chiral salicyloxazoline and cobalt acetate tetrahydrate as an inexpensive catalyst. Notably, the kinetic resolution process was also achieved with s factors up to 347.8. Experimental, kinetic and computational studies on cobalta-electrocatalysis provide insights into the catalyst's working mode. [ABSTRACT FROM AUTHOR]

We describe herein an intriguing method for the synthesis of biaryl aldehydes bearing both axial and central chirality through a desymmetric [3 + 2] cycloaddition reaction of activated isocyanides with prochiral biaryl dialdehydes under silver catalysis. This protocol features excellent enantioselectivity, 100% atom economy, good functional group compatibility, and operational simplicity. [ABSTRACT FROM AUTHOR]

An efficient method for the construction of various 3,4,5-trisubstituted phenol derivatives has been achieved via the Rh(III)-catalyzed coupling of phosphonium cations with internal alkynes. This protocol shows good substrate compatibility, as an array of structurally and electronically diverse phosphonium compounds react efficiently with up to 87% yield. [ABSTRACT FROM AUTHOR]

Alcohols and nitrile derivatives are highly important skeletons, widely applied in both organic and bioorganic chemistry. Cross coupling of alcohols and nitriles through formal conjugated addition is a powerful and environmentally friendly strategy for access to long carbon chain tethered nitriles, due to its 100% atom economy and readily available starting materials. Herein, we reported a first example of the pincer manganese(I) catalyzed redox-neutral coupling of nitriles with allylic alcohols to forge a variety of δ-hydroxynitriles. The reaction featured a broad substrate scope with good functional group tolerance under simple conditions (43 examples, 50–94% yields). Remarkably, the mildness and practicality of this protocol were further demonstrated by the successful synthesis of anipamil and verapamil via a one or two-cascade borrowing hydrogen procedure. [ABSTRACT FROM AUTHOR]

The Zn,Co bimetallic organic skeleton material ZIF-11(Zn/Co) with different molar ratios was synthesized at room temperature by a one-pot method as a catalyst for the activation of persulfate (PMS) degradation of tylosin (TYL). By comparing the experimental systems of ZIF-11, ZIF-11(Zn/Co)-2, persulfate, and ZIF-11(Zn/Co)-2/PMS, the experimental system with the best effect was selected for subsequent research. X-Ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and specific surface area and porosity analyses were used to describe and characterize the properties of the catalysts. A certain concentration of TYL solution was chosen as the experimental sample, and the pollutant concentration, pH, catalyst dosage, persulfate dosage and reaction temperature were used as the experimental conditions. The influence factors of catalytic removal of TYL by ZIF-11(Zn/Co)-2/PMS were studied. The specific mechanism of catalytic degradation of TYL was investigated using the results of free radical quenching experiments. The results showed that, under acidic conditions and at higher temperatures, the removal rate of bimetal ZIF-11(Zn/Co)-2 to TYL (40 mg L−1) within 30 min reaches more than 80%. Experiments showed that the catalyst has good reusability. According to the data analysis after the addition of a free radical quenching agent in the experimental process, it can be seen that the sulfate free radical plays a leading role in the entire experimental system. [ABSTRACT FROM AUTHOR]

A rhodium-catalyzed electrochemical regioselective annulation of 6-phenylpurines and 6-phenyl-7-deazapurines with alkynes has been developed. Electricity is used to recycle the active rhodium-based catalyst, promote the evolution of H2 and help in reducing the reaction temperature. This mild and green method enables a broad substrate scope and wide functional group tolerance, providing a new series of polycyclic purinium and 7-deazapurinium salts in high yields. Mechanistic studies show that the five-member rhodium(III) species and purinoisoquinolinium-coordinated rhodium(I) complex are the two key intermediates in this transformation. [ABSTRACT FROM AUTHOR]

The catalytic reaction of biaryl lactams with activated isocyanides is reported for the first time. By employing a cooperative catalytic system, oxazole-containing axially chiral biaryl anilines were obtained in high yields with excellent enantioselectivities. The key to the success lies in the atroposelective amide C–N bond cleavage with activated isocyanides. [ABSTRACT FROM AUTHOR]

Organosulfurs are important commodity chemicals and indispensable synthetic intermediates in modern chemistry that were traditionally synthesized using metal catalysts, oxidants or strong bases, which caused numerous environmental pollution issues. The divergent synthesis of these scaffolds via a single catalysis under catalyst and oxidant free conditions is a fantastic idea to overcome these drawbacks. Here, we report a safe, practical and eco-friendly electrochemical methodology for the controllable dechloro-coupling of 1,2-dichloroethane (DCE) with thiols, providing value-added β-chloroethylsulfurs, which serve as versatile building blocks in the efficient late-stage conversion to bioactive molecules. The mildness and practicality of this protocol was further demonstrated by the total synthesis of anti-gout drug sulfinpyrazone in a 32% total yield over three steps. [ABSTRACT FROM AUTHOR]

A safe, practical and eco-friendly electrochemical methodology for the synthesis of 3-formylated indoles has been developed by the utilization of Me3N as a novel formylating reagent. Stoichiometric oxidants, metal catalysts, and activating agents were avoided in this method, and an aqueous biphasic system of n-Bu4NBF4/PEG-400/H2O was used as a recyclable and reusable reaction medium, which made this electrosynthesis approach more sustainable and environmentally friendly. This process expanded the substrate scope and functional group tolerance for both N-EDG and N-EWG indoles. Furthermore, late-stage functionalization and total/formal synthesis of drugs and natural products were realized by means of this route. [ABSTRACT FROM AUTHOR]

An enantioselective synthesis of highly functionalized 1,4-dihydropyrazolo[4′,3′:5,6]pyrano[2,3-b]quinolines from modified MBH carbonates and pyrazolones via a chiral phosphine-mediated alkylation/annulation sequence has been realized. The chiral dihydropyrano[2,3-c]pyrazoles bearing bio-active condensed heterocycles were facilely formed in good chemical yields and with high to excellent enantioselectivity by utilizing low catalyst loading. [ABSTRACT FROM AUTHOR]

The diethylenetriamine (DETA) impregnated modified attapulgite hybrid ZIF-8 composite has been developed as a new type of amine-impregnated hybrid MOF adsorbent for the adsorption of aspirin and ibuprofen in aqueous solution. ZIF-8 was first successfully grafted onto attapulgite and amine was impregnated into the hybrid material to successfully prepare the nanocomposite material (ATP@ZIF-8-DETA). By comparing the removal effects of different materials toward aspirin and ibuprofen, a highly efficient adsorbent (ATP@ZIF-8-DETA-20) was selected for follow-up research. The composite material was characterized by FT-IR, XRD, SEM and BET measurements. The research results indicate that the adsorption capacity of ATP@ZIF-8-DETA-20 for aspirin may be as high as 350.88 mg g−1. The new composite material (ATP@ZIF-8-DETA-20) has excellent efficiency and reusability, and show great potential for adsorbing nonsteroidal anti-inflammatory drugs (NSAIDs) in aqueous solutions. [ABSTRACT FROM AUTHOR]

An efficient and eco-friendly electrochemical synthesis of various sulfinic esters from thiols and alcohols via sequential S–H/S bond cleavage and double S–O bond formation under mild reaction conditions has been developed. Stoichiometric oxidants, metal catalysts, activating agents and even added bases were avoided in this method, and the only by-product generated from this reaction was dihydrogen gas which could serve as a green source of energy. Various functional groups are compatible with this green protocol which can be easily conducted on a gram-scale. [ABSTRACT FROM AUTHOR]

The reaction of a new pentadentate Schiff base hydrazide ligand, (E)-methyl N′-(2-hydroxy-3-methoxybenzylidene)hydrazinecarboxylate (HL), with lanthanide nitrate, and sodium acetate in the presence of triethylamine, resulted in a novel family of octanuclear neutral compounds, [Ln8(μ3-O)4(L)8(CH3COO)4(CO3)2]·xH2O, where Ln = Gd (1), Tb (2), Dy (3), or Ho (4). Compounds 1–4 contained two unusual Ln4 boat-shaped units, which were held by four L− chelating ligands, two μ3-O2−, and one μ4-CO32−. These structures were interconnected by four CH3COO− ions, forming a novel Ln8 cluster. Magnetic studies revealed antiferromagnetic Gd…Gd interactions in Gd8, which exhibited a significant magnetocaloric effect and a magnetic entropy change as large as 32.49 J K−1 kg−1 at a field of 7 T at 2 K. In addition, Dy8 exhibited a frequency dependent slow relaxation of magnetization at a zero applied direct current magnetic field. [ABSTRACT FROM AUTHOR]

In this work, we present a new type of functional organic/inorganic hybrid supraparticle that spontaneously assembles from silver ions (Ag+), iodide ions (I−) and thioflavin T (ThT) under aqueous solution conditions. ThT alone in aqueous solution was weakly fluorescent with an emission band at 494 nm, which was related to the monomer. However, in the above-mentioned hybrid supraparticle (i.e., ThT@AgI SP) structure, the ThT monomer can form a dimer with a new emission band. The new band shifted to 546 nm and the emission intensity increased. We further present a facile strategy of reversible fluorescence switching of ThT by a simple cation (Ag+) and anions (I− and S2−), which can be employed for the ratiometric fluorescence detection of Ag+ with high sensitivity and selectivity. The linear range of detecting Ag+ was from 100 nM to 10 μM, with a limit of detection as low as approximately 50 nM. Moreover, it can be successfully applied for the operation of a logic gate system and to the sensing of Ag+ in real water samples. [ABSTRACT FROM AUTHOR]

In this work, a label-free molecular beacon (MB)-like biosensor is designed for the determination of H2O2 and glucose based on the fluorescence regulation of Hoechst dyes hosted by the designed AT-rich single-stranded DNA (ssDNA), in which Hg2+ and cysteine (Cys) act as activators. The designed AT-rich ssDNA (ATprobe) can be directed to form a hairpin with an Hg2+-induced T–Hg2+–T complex, which provides a medium for enhancing the fluorescence of Hoechst dyes significantly. On the other hand, Cys can effectively grab Hg2+ from the T–Hg2+–T complex by thiol–Hg2+ interactions, destructing the hairpin and then switching the Hoechst dyes to the fluorescence “off” state. Combined with these properties, we have demonstrated its application for label-free fluorescence “turn on” detection of H2O2. The sensing mechanism is based on the specific reaction between H2O2 and Cys catalyzed by I−, the resulting disulfide reverses the Cys-mediated fluorescence decrease of the MB-hosted Hoechst dyes. The approach achieves a low detection limit of 0.1 μM for H2O2. Moreover, this method is further applied to the noninvasive detection of glucose in artificial saliva and urine samples, combining with glucose oxidase (GOx) for the oxidation of glucose and formation of H2O2. Compared to traditional methods, the proposed design is cost-effective, simple to prepare and manipulate without fluorescence labeling or chemical modification. [ABSTRACT FROM AUTHOR]

A novel lanthanide coordination polymer nanoparticle (LCPN)-based ternary complex was synthesized via the self-assembly of a terbium ion (Tb3+) with a nucleotide (GMP) and a mercury ion (Hg2+) in aqueous solution. The as-prepared LCPN-based ternary complex (Tb-GMP-Hg) can be applied to the development of time-resolved luminescence assays and oxidase-based biosensors. [ABSTRACT FROM AUTHOR]

Correction for 'Enantioselective synthesis of functionalized 1,4-dihydropyrazolo-[4′,3′:5,6]pyrano[2,3-b]quinolines through ferrocenyl-phosphine-catalyzed annulation of modified MBH carbonates and pyrazolones' by Xiao Xiao et al., Chem. Commun., 2021, DOI: 10.1039/d1cc00989c. [ABSTRACT FROM AUTHOR]

3d-Metal catalyzed borrowing hydrogen (BH) reactions represent powerful and environmentally friendly approaches for the direct coupling of alcohols with nitriles to assemble various important branched nitriles. The development of simple and efficient ligands is a crucial issue in this field. In this study, we designed a series of readily available N , N -bidentate ligands that demonstrated good efficiency in the Mn-catalyzed BH reaction of alcohols and nitrile derivatives, yielding the targeted nitriles in moderate to good yields. Remarkably, the mildness and practicality of this protocol were further demonstrated by the successful synthesis of anipamil via a two-cascade borrowing hydrogen procedure., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The iridium/ f -diaphos L1, L5 or L12 catalyzed asymmetric hydrogenation of 2-imidazolyl aryl/alkyl ketones to afford two enantiomers of the desired chiral alcohols with high conversions (up to 99% yield) and moderate to excellent enantioselectivities (61% - >99% ee ) was realized for the first time. This protocol could be easily conducted on a gram-scale with a TON of 9700.

An enantioselective synthesis of highly functionalized 1,4-dihydropyrazolo[4',3':5,6]pyrano[2,3-b]quinolines from modified MBH carbonates and pyrazolones via a chiral phosphine-mediated alkylation/annulation sequence has been realized. The chiral dihydropyrano[2,3-c]pyrazoles bearing bio-active condensed heterocycles were facilely formed in good chemical yields and with high to excellent enantioselectivity by utilizing low catalyst loading.

The first example of the metal- and solvent-free B(C6F5)3-catalyzed Markovnikov addition of indoles to aryl alkynes was disclosed. Both N-H and N-protected indoles were tolerated, leading to a wide spectrum of versatile bis(indolyl)alkanes in moderate to good yields with high regioselectivities.

In this work, a label-free molecular beacon (MB)-like biosensor is designed for the determination of H2O2 and glucose based on the fluorescence regulation of Hoechst dyes hosted by the designed AT-rich single-stranded DNA (ssDNA), in which Hg(2+) and cysteine (Cys) act as activators. The designed AT-rich ssDNA (ATprobe) can be directed to form a hairpin with an Hg(2+)-induced T-Hg(2+)-T complex, which provides a medium for enhancing the fluorescence of Hoechst dyes significantly. On the other hand, Cys can effectively grab Hg(2+) from the T-Hg(2+)-T complex by thiol-Hg(2+) interactions, destructing the hairpin and then switching the Hoechst dyes to the fluorescence "off" state. Combined with these properties, we have demonstrated its application for label-free fluorescence "turn on" detection of H2O2. The sensing mechanism is based on the specific reaction between H2O2 and Cys catalyzed by I(-), the resulting disulfide reverses the Cys-mediated fluorescence decrease of the MB-hosted Hoechst dyes. The approach achieves a low detection limit of 0.1 μM for H2O2. Moreover, this method is further applied to the noninvasive detection of glucose in artificial saliva and urine samples, combining with glucose oxidase (GOx) for the oxidation of glucose and formation of H2O2. Compared to traditional methods, the proposed design is cost-effective, simple to prepare and manipulate without fluorescence labeling or chemical modification.

A novel lanthanide coordination polymer nanoparticle (LCPN)-based ternary complex was synthesized via the self-assembly of a terbium ion (Tb(3+)) with a nucleotide (GMP) and a mercury ion (Hg(2+)) in aqueous solution. The as-prepared LCPN-based ternary complex (Tb-GMP-Hg) can be applied to the development of time-resolved luminescence assays and oxidase-based biosensors.