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Study of the intramolecular aza-Michael addition reaction from an aminofluorovinylsulfone opens a new route for the synthesis of pyrrolidine derivatives. An unexpected diastereoselective cyclization reaction was observed, leading preferentially to the anti-N-benzylpyrrolidine sulfone. The resulting sulfone was reacted with aldehydes to access β-substituted α-fluoroalkenyl pyrrolidines in one step.

The title synthesis is successfully performed using benzylic, heterobenzylic or aliphatic alcohols as well as phenol or catechol as the substrates.

A strategy for cross-electrophile coupling has been developed via the merger of photoredox and transition metal catalysis. In this report, we demonstrate the use of commercially available tris(trimethylsilyl)silane with metallaphotoredox catalysis to efficiently couple alkyl bromides with aryl or heteroaryl bromides in excellent yields. We hypothesize that a photocatalytically generated silyl radical species can perform halogen-atom abstraction to activate alkyl halides as nucleophilic cross-coupling partners. This protocol allows the use of mild yet robust conditions to construct Csp3–Csp2 bonds generically via a unique cross-coupling pathway.

A variety of the title γ-butyrolactones (IV) (39 examples) are synthesized by Co-catalyzed three-component reaction of itaconate (I) with carbonyl compounds and aryl bromides.

The reaction yields dramatically depend on the experimental procedure requiring the addition of most of the anisole derivative over 24 h to a mixture of a small amount of the anisole derivative and all other reagents.

α-Chloro(diazo)acetate can be readily used in an intermolecular ring expansion catalyzed by a boron Lewis acid to construct α-chlorinated medium-size cyclic ketones. This intermolecular Tiffeneau–Demjanov reaction proceeds in good yield from easily prepared or commercially available starting materials and allows the concomitant formation of a tetrasubstituted stereocenter.

A new and efficient rhodium/copper-cocatalyzed C–H oxidation reaction of isoquinolinium N-amides has been developed. In the presence of rhodium(II) acetate dimer, copper(II) chloride, a ligand and sodium tert-butoxide, a variety of isoquinolin-1-ones were prepared in moderate to good yields via ortho C–H oxidation.

Two novel 2,5-diphenyl oxazole derivatives, named gymnothecaoxazoles A (1) and B (2), were isolated from the whole parts of endemic medicinal plant of Gymnotheca chinensis (Saururaceae). The structures of the new compounds were elucidated by extensive NMR and MS data, and the structure of compound 1 was further confirmed by X-ray crystal diffraction analysis.

The title compound (I), called perovskiaol, exhibits significant cytotoxic activity inhibiting NB4, A549 as well as HepG2 cells.

The α-alkylation of unactivated amides with alcohols is described. Using a NCP-type pincer Ir complex as the precatalyst and KOtBu as the base, the reactions of secondary or tertiary acetamides with benzyl or nonbenzyl primary alcohols occur at 80 °C, furnishing the alkylation products in good yields. This method represents a practical and green means of α-alkylation of amides in a relatively mild, efficient, and selective manner with low catalyst loadings (0.5 mol %).

An efficient pathway for the synthesis of the aminobenzophenone derivatives via Friedel–Crafts benzoylation using copper triflate as catalyst is proposed. New derivatives are synthesized. The copper triflate could be easily recovered and reused without loss of catalytic activity. Both the use of ionic liquids and microwave heating turned out to be fruitful.

The title reaction proceeds under very mild reaction conditions and can provide various substituted 10-allylanthrones in excellent yields and excellent chemo-, regio-, and enantioselectivities.

Two new series of pyran- or coumarin-substituted thiazolyl-pyrazole-chromen-2-one derivatives 10a–10d and 11a–11d were efficiently synthesized under environmentally friendly reaction conditions through a convenient one-pot multicomponent reaction of a heterocyclic bromoacetyl derivative 3 or 4 with thiosemicarbazide and a substituted 3-(acetoacetyl)coumarin derivative 5a–5d in anhydrous ethanol. The reaction proceeds through Hantzsch thiazole and Knorr pyrazole syntheses in refluxing ethanol. The key features of this approach are its operational simplicity, the quick access to the desired products, and the good to excellent yields. The structures of the newly synthesized compounds were established by IR spectroscopy, 1H, 13C, and 2D NMR spectroscopy, and mass spectrometry.

Combined experimental and theoretical investigations into the phenyliodine bis(trifluoroacetate) (PIFA)-mediated reaction of N-arylcinnamamide to produce 3-arylquinolin-2-one derivatives have been conducted. High regioselectivity during the aryl migration process was observed in 3,3-disubstituted acrylamides. Density functional theory calculation was conducted in an attempt to understand the mechanism and the origin of the regioselectivity. On the basis of both the experimental and the theoretical results, a mechanism involving an oxidative annulation, followed by an aryl migration, has been proposed. The annulation is the regioselectivity determining step.

A highly enantioselective palladium/l-proline-catalyzed α-arylative desymmetrization of cyclohexanones was developed. The new strategy for α-arylation reaction led to a series of optically active morphan derivatives bearing α-carbonyl tertiary stereocenters in good yields with excellent enantioselectivities (up to 99% ee).

A rhodium-catalyzed asymmetric synthesis of 5,5-disubstituted cyclohexa-1,3-dienes has been achieved by [2+2+2] cycloaddition reactions between diynes and Morita-Baylis-Hillman (M-B-H) adducts as unsaturated substrates. Products containing two adjacent chiral centres (quaternary and tertiary, respectively) were obtained with complete diastereoselectivity and high enantioselectivity (84-97%) through a kinetic resolution of the M-B-H adduct. Furthermore, these highly substituted cyclohexadienes reacted with dienophiles to afford the corresponding Diels-Alder cycloadducts in good yields

A synthetic method to prepare cycloalkyl-, piperidinyl- and pyranyl-fused pyrroles efficiently by gold(I)-catalyzed dehydrative aminoalkenylation of β-amino-1,n-diynols under mild conditions at room temperature is described.

An original and rapid domino reaction for access to oxazolidin-4-ones is presented. Simply by heating α-bromoamido alcohol in the presence of KNaCO3 and water with readily prepared Michael acceptors, an unprecedented molecular rearrangement is generated. This new methodology enables the hitherto unreported synthesis of functionalized oxazolidin-4-ones. The process was proved to be compatible with a wide variety of substrates, and high regioselectivities were achieved.

By using carbon tetrachloride as the chloride radical and boron trifluoride etherate as the Lewis acid, the halogen-light-activated anomeric inversion of glycoside was achieved. This reaction is a novel guide to invert the glycosidic bond from a β-anomer to an α-anomer.

Thoreliolides A and B, two new polyisoprenylated benzoylphloroglucinol derivatives with a novel carbon skeleton, together with four known compounds, were isolated from the fruits of Calophyllum thorelii and their structures elucidated using spectroscopic methods. Thoreliolide B showed moderate activity against three cancer cell lines, MCF-7, HeLa and NCI-H460, with IC 50 values of 9.7, 16.6 and 24.2 μg/mL, respectively, using the sulforhodamine B assay.

[CholineCl][ZnCl2]3, a deep eutectic solvent between choline chloride and ZnCl2, has been used as a dual function catalyst and green solvent for the Friedel–Crafts acylation of aromatic compounds instead of using the moisture-sensitive Lewis acids and volatile organic solvents. The reactions are performed with high yields under microwave irradiation with short reaction times for the synthesis of ketones. Interestingly, indole derivatives are regioselectively acylated in the 3-position under mild conditions with high yields without NH protection. Three new ketone products are synthesized. [CholineCl][ZnCl2]3 is easily synthesized from choline chloride and zinc chloride at a low cost, with easy purification and environmentally benign compounds. [CholineCl][ZnCl2]3 can be reused up to five times without loss of catalytic activity, making it ideal in industrial processes.

Antibiotic resistance is a worldwide public health threat that needs to be addressed by improved antibiotic stewardship and continuing development of new chemical entities to treat resistant bacterial infections. Compounds that work alongside known antibiotics as combination therapies offer an efficient and sustainable approach to counteract antibiotic resistance in bacteria. Guided by property-based analysis, a series of aza-tricyclic indolines (ATIs) were synthesized to optimize their physiochemical properties as novel combination therapies with β-lactams to treat methicillin-resistant S. aureus (MRSA) infections. A novel and highly efficient gold-catalyzed tandem cyclization was developed to facilitate the synthesis of these ATIs. One guanidine-containing ATI was discovered to possess both improved anti-MRSA activity and lower mammalian toxicity both in vitro and in vivo. In addition, it also showed significantly enhanced aqueous solubility and metabolic stability. These results indicated that the ATIs are a novel class of anti-MRSA agents suitable for further evaluations as adjuvant therapy in animal model studies.

From multi-substituted 8-aminoimidazo[1,2-a]pyrazines, prepared via modified Groebke–Blackburn–Bienayme reaction, a Pd-catalyzed cyclization reaction was discovered, leading to a rare (Z)-4,5-dihydro-3H-[1,3]diazocine system. Conditions of this cyclization were screened and DMF solvent was found as one of the key factors for the cyclization.

Ansalactams B—D exhibit weak antibacterial activity against methicillin-resistant S.aureus (MRSA).

The highly efficient and direct asymmetric reductive amination of arylacetones catalyzed by an iridium complex for the preparation of enantiomerically pure β-arylamines is described. The monodentate phosphoramidite ligand exhibits superb reactivity (TONs of up to 20 000) and enantioselectivity (up to 99 % ee). Additives played important roles in this reductive coupling reaction.

Double translocation processes in homo- and heterobimetallic bis-strap porphyrin complexes rely on the coexistence of two different coordination modes namely out-of-plane (OOP, bound to the N-core) and hanging-atop (HAT, bound to the strap). Two different dynamics were encountered: (i) the metal ions stay on their respective side of the macrocycle while exchanging between the strap and N-core binding sites (compartmentalized process); (ii) the metal ions exchange between the two sides of the porphyrin and maintain their OOP/HAT coordination modes (non-compartmentalized process). Various stimuli were used to tune these dynamic bimetallic systems (allosteric effector, acid–base conditions, dynamic constitutional evolution, light exposure).

A Cu-mediated regioselective, dehydrogenative homocoupling of indoles was developed using AgNO3 as the additive. The easily installed and removed N-pyrimidyl group exerted complete C2 regiocontrol via C–H activation. A series of indole substrates underwent cross-dehydrogenative-homocoupling. This work developed an effective approach for the synthesis of 2,2′-biindole core of a number of chemicals fundamentally important in material and pharmaceutical chemistry.

Energetic materials (explosives, propellants, and pyrotechnics) are used extensively for both civilian and military applications and the development of such materials, particularly in the case of energetic salts, is subject to continuous research efforts all over the world. This Review concerns recent advances in the syntheses, properties, and potential applications of ionic salts based on tetrazole N-oxide. Most of these salts exhibit excellent characteristics and can be classified as a new family of highly energetic materials with increased density and performance, alongside decreased mechanical sensitivity. Additionally, novel tetrazole N-oxide salts are proposed based on a diverse array of functional groups and ions pairs, which may be promising candidates for new energetic materials.

The (benzenesulfonyl)difluoromethylsulfanyl (PhSO2CF2S) group is a valuable substituent with specific properties which can provide access to new applications of fluoroalkylthiolated compounds. Direct introduction of this moiety can be performed by in an electrophilic manner by using a new shelf-stable reagent, namely a (benzenesulfonyl)difluoromethanesulfenamide. Furthermore, mild magnesium-mediated reduction of the PhSO2CF2S group leads to a facile synthesis of difluoromethylthiolated molecules and their deuterated analogs.

A crystalline copper-based metal-organic framework Cu/MOF-74 was synthesized, and used as an efficient heterogeneous catalyst for the synthesis of 1,2-dicarbonyl-3-enes by means of the hydroacylation of 1-alkynes with glyoxal derivatives in the presence of a base. Cu/MOF-74 was found to be more catalytically active for the synthesis of 1,2-dicarbonyl-3-enes than other MOFs including Cu2 (BDC)2 (DABCO), Cu3 (BTC)2 , Cu(BDC), Cu2 (NDC)2 (DABCO), Cu4 I4 (DABCO)2 , Ni-MOF-74, Zn-MOF-74, Fe3 O(BDC)3 , In(OH)(BDC), and Zr6 O4 (OH)4 (BDC)6 . Cu/MOF-74 also exhibited better performance than other homogeneous copper catalysts, including Cu(OAc)2 , Cu(NO3 )2 , CuI, CuBr, CuCl, CuCl2 , and CuBr2 . The Cu/MOF catalyst was able to be recovered and reused several times without a significant degradation in catalytic activity. To the best of our knowledge, the formation of 1,2-dicarbonyl-3-enes has not previously been carried out under heterogeneous catalysis conditions.

In recent years, great efforts have been devoted to the synthesis and modification of layered zeolites, a new family of microporous crystalline materials that are viewed as covalently bonded continuous frameworks extended in only two dimensions. This leads to a very interesting and attractive research area in porous materials science, since the stacking modes of zeolite layers could be constructed into various types of structures by direct synthesis or postsynthetic treatments, endowing zeolitic materials with structural diversity. The potential of layered zeolite precursors for generating hierarchical catalysts or incorporating organic functional groups into two dimensional structures is of particular interest. In this contribution, the most attractive achievements in the research area of layered zeolites are summarized, including synthetic approaches, strategies for modification of layered structures and catalytic applications. Last but not least, the challenges for future research on these types of porous materials are proposed.

This review aims to highlight the most significant recent developments in the synthesis of pyridinofused azacrown ethers, which contain a minor azaheterocyclic moiety contributing its nitrogen atom to the macrocycle. This subfield of azacrown ethers draws constant attention of scientists over the last decades owing to their great theoretical and practical potential.1 Pyridinocrownophanes, azacrown ethers containing a pyridine subunit, are widely used as ligands for effective metal ion sequestration,2 as well as enantiomeric recognition.3 They are also excellent phase-transfer catalysts,1 membrane ion transporting vehicles,4 scaffolds for the design of organic sensors, nanosized on-off switches, and other molecular devices.5 Certain pyridinoazacrown compounds have been found to possess antibacterial6 and anticancer properties.7

Michael addition of α-cyanoketones and acrylates in the presence of chiral cinchonidine catalyst (CJN) produces the corresponding Michael adducts in high yields with moderate to good enantioselectivities.

One life, two strategies: Crucial structural differences between the human and the Plasmodium falciparum proteasomes were recently identified. A combination of cryo-EM and functional characterization enabled the design of a selective antimalarial proteasome inhibitor that shows low toxicity in the host. When used with artemisinin, this ligand offers a new approach for the efficient treatment of malaria at all stages of the parasite lifecycle.

A novel and efficient iron-catalyzed cyclization of ketoxime carboxylates and N,N-dialkylanilines for the modular synthesis of diverse pyridines was developed. The reaction was initiated by Fe-catalyzed N–O bond cleavage of ketoxime carboxylates in the presence of tertiary anilines. The methylene carbon on N,N-dialkylanilines functioned as a source of one-carbon synthon in the reaction. The reaction used readily available starting materials, tolerated various functional groups, and afforded 2,4-disubstituted and 2,4,6-trisubstituted pyridines in good to high yields under mild conditions.

We demonstrated a unique copper-rich open-framework chalcogenide constructed from icosahedral Cu8Se13 and octahedral Cu4Se6 nanoclusters connected to each other through a SnSe3(Se2) bridging unit. The specific copper-rich composition gives rise to a narrow band gap and photoelectrical responsive properties in the infrared range.

Cinnamic acid derivatives (CAs), which have proven to be versatile components, are present in abundance in biologically active natural products, and are widely used as intermediates in the manufacture of pharmaceuticals, and chemicals. The presence of cis- and trans-CAs created difficulties for natural product and organic synthetic studies. A highly efficient method that utilized iodine to entirely convert cis- CAs into their trans-forms was developed to solve this problem. The mechanism of study revealed this conversion occurred via an anti-diiodo intermediate.

Chemical investigation of Acanthopanax koreanum leaves resulted in the isolation of 13 compounds (1-13), including six new (20,29)-dehydrolupane-type triterpenoids: 3α,11α,30-trihydroxylup-20(29)-en-23,28-dioic acid (1), 3α,11α,30-trihydroxylup-20(29)-en-28-oic acid (2), 3α,11α,30-trihydroxylup-23-al-20(29)-en-28-oic acid (3), 3α, 11α-dihydroxy-20-oxo-30-norlupane-23,28-dioic acid (5), (20S)-3α-hydroxy-30 oxolupane-23,28-dioic acid (8), (20S)-3β,7β,29-trihydroxy-lupane-23-al-28-oic acid (10), and one novel compound isolated for the first time, named 3α,20α,29-trihydroxylupane-23,28-dioic acid (9), together with six known compounds (4, 6, 7, and 11-13). Chemical structures of the isolated compounds were evaluated by analyzing and comparing spectroscopic data with those reported in the literature. These compounds were also evaluated for their tyrosinase inhibitory effects. Among them, compounds 3, 7, 9, and 12 showed significant inhibitory effects, with inhibitory concentrations of 50% (IC50) values ranging from 8.61 to 63.5 μM.

An efficient and straightforward regio-controlled route to β-fluoro-γ-chlorinated amines was developed via an ammonium–chloronium superelectrophilic activation in superacid HF/SbF5. Through halogen directing effect the method was extended to a variety of (poly)halofluorinated building blocks amenable for further synthetic modifications. The direct synthesis of chlorofluorinated analogues of bioactive compounds via this process confirmed the ability to use this strategy for further applications in medicinal chemistry.

The title compound, Ca2+xNd8–x(SiO4)6O2–0.5x (x = 0.49), was synthesized at 1873 K and rapidly quenched to room temperature. Its structure has been determined using single-crystal X-ray diffraction and compared with results reported using neutron and X-ray powder diffraction from samples prepared by slow cooling. The single-crystal structure from room temperature data was found to belong to the space group P63/m and has the composition Ca2.49Nd7.51(SiO4)6O1.75 [dicalcium octa­neodymium hexa­kis­(ortho­silicate) dioxide], being isotypic with natural apatite and the previously reported Ca2Nd8(SiO4)6O2 and Ca2.2Nd7.8(SiO4)6O1.9. The solubility limit of calcium in the equilibrium state at 1873 K was found to occur at a composition of Ca2+xNd8–x(SiO4)6O2–0.5x, where x = 0.49.

Efficient strategies for the regioselective ortho acetoxylation/alkoxylation of C–H bond of azoxybenzenes in the presence of palladium catalysts were developed using PhI(OAc)2 as the teminal oxidant. Under the very similar conditions established, both reactions proceeded smoothly and were tolerated by a variety of functional groups.

The structure of the Ruddlesden–Popper layered perovskite Li2CaTa2O7, known for its high photocatalytic water activity since its discovery in 2008, is reinvestigated. This oxide has been characterized by powder X-ray and neutron thermodiffraction, TEM, second harmonic generation (SHG), and Raman experiments on powders and single crystals. It is shown that it undergoes two structural phase transitions (i) around 220 °C, mainly characterized by the progressive emergence of SHG signal at low temperatures, and (ii) at 660 °C, mainly characterized by changes of the temperature behavior of lattice parameters and by the emergence of Raman signals that linearly increase on decreasing temperature. It is shown by powder neutron diffraction profile refinements at RT, 400, and 800 °C that the space groups of the successive phases of Li2CaTa2O7 are the acentric Pna21 (RT ≤ T ≤ 220 °C), Pnma (220 °C ≤ T ≤ 660 °C), and Cmcm (T ≥ 660 °C). A soft mode associated with the transition to the highest symmetry for this structu...

The use of the ITent-based series of Pd-N-heterocyclic carbenes precatalysts (Tent= Tentacular) enables the Buchwald–Hartwig amine arylation reaction in apolar alkane solvents. The use of such solvents is rare because of their poor solvation properties. Nonetheless, they could be of interest for industrial applications, as they can be disposed of in an energetically favorable manner and may potentially simplify product isolation. The excellent solubility of the precatalysts permitted the desired products to be obtained in yields ranging from 75 to 96 %, even with deactivated and functionalized coupling partners.

A new and efficient method for the construction of 2,3,4-trisubstituted 2H-pyrrolo[3,4-c]quinoline derivatives was developed. Starting from easily accessible 2-azidobenzaldehyde, nitromethane, 1,3-dicarbonyl compounds, and various amines gave the multicomponent reaction (MCR) products, 1-substituted 3-acyl-4-(2-azidophenyl)-2-methyl-1H-pyrroles, that underwent Staudinger/aza-Wittig cyclization of in the presence of triphenylphosphine to give the final products.