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Palladium‐catalyzed thioesterification of (aza)indole‐tethered aryl iodides, Mo(CO)6, and sulfonyl chlorides is reported. A series of C2 thioester‐group substituted indoline‐fused ring compounds are constructed by an intramolecular Heck cyclization and carbonylation chemistry involving N‐(2‐iodobenzoyl)indole. The salient features of this three‐component cascade sequence include the use of solid Mo(CO)6 as the carbon monoxide source and good functional group tolerance. [ABSTRACT FROM AUTHOR]

A procedure utilizing [TBA][P(SiCl3)2] as P source for the synthesis of phosphinecarboxamides is presented. The synthesis involves the reaction of [TBA][P(SiCl3)2] with isocyanates. These compounds act as highly effective reagents for the subsequent phosphination of isocyanates, leading to the formation of phosphine(triscarboxamides). This reaction proceeds swiftly under mild and straightforward conditions, making it suitable for a wide range of commercially available isocyanates. [ABSTRACT FROM AUTHOR]

As a gasotransmitter, carbon monoxide can induce tumor cell apoptosis by reversing the Warburg effect. Carbon monoxide-releasing molecules (CORMs) are a promising option for CO administration, but how to deliver the threshold concentration of CO into the tumor tissue remains a challenge. A series of novel targeted CORMs combining glycyrrhetinic acid (GA) derivative conjugates with a lipophilic mitochondriotropic triphenylphosphonium cation (TPP+) moiety were synthesized and evaluated for their antitumor activities. Among the complexes, complex 2 possessed excellent antitumor activities in HepG2 cells with IC50 values of 12.18 ± 4.66 μM compared with 5-FU. It caused the production of reactive oxygen species and reduced the mitochondrial membrane potential against HepG2 cells. Western blot analysis showed that complex 2 up-regulated the expression of the Bax protein and down-regulated the expression of Bcl-2, activated caspase-3, and HO-1. The docking study demonstrated that complex 2 can interact with the Bcl-2 protein through hydrophobic interaction and hydrogen bonds. The aforementioned results indicated that complex 2 triggered cell apoptosis through a mitochondrial pathway. These results suggest that the complexes may be promising anticancer agent candidates. [ABSTRACT FROM AUTHOR]

A novel and facile method for the formation of C–S bonds via Mn(III) promoted cross-coupling reaction of disulfides with dialkyl phosphites under mild reaction conditions has been achieved. This strategy allows various dialkyl phosphites and disulfides to be transferred into the desired products in good to excellent yields. [ABSTRACT FROM AUTHOR]

C2‐functionalized pyrimidine derivative is a family of important nitrogen heterocyclic compounds due to their unique structure and multiple reaction sites. In this work, a novel method for the synthesis of C2‐functionalized pyrimidine derivatives through phenylalkynes and pyrimidine disulfides under ambient conditions is proposed. The reaction can be triggered by adding catalytic amounts of cesium fluoride, which is characterized by free‐catalyst and special activator. Importantly, this reaction has good compatibility with substrates substituted by electron‐donating and electron‐withdrawing groups at C4. Density functional theory (DFT) calculations also indicates that the production of C2‐functionalized pyrimidine derivatives is more favourable. [ABSTRACT FROM AUTHOR]

SP 1 sp H NMR (400 MHz, CDCl SB 3 sb ): = 7.73-7.67 (m, 1 H), 7.60-7.58 (m, 2 H), 7.51-7.49 (m, 1 H), 7.34-7.29 (m, 2 H), 7.16 (d, I J i = 7.9 Hz, 2 H), 2.34 (s, 3 H). SP 1 sp H NMR (400 MHz, CDCl SB 3 sb ): = 8.46 (d, I J i = 5.2 Hz, 1 H), 7.68-7.66 (m, 1 H), 7.63-7.58 (m, 1 H), 7.43-7.41 (m, 2 H), 7.14-7.06 (m, 3 H), 2.31 (s, 3 H). SP 1 sp H NMR (400 MHz, CDCl SB 3 sb ): = 7.89 (d, I J i = 8.0 Hz, 1 H), 7.80 (d, I J i = 8.0 Hz, 1 H), 7.67-7.63 (m, 2 H), 7.46-7.42 (m, 1 H), 7.36-7.32 (m, 1 H), 7.06-7.02 (m, 2 H). SP 1 sp H NMR (400 MHz, CDCl SB 3 sb ): = 7.43 (d, I J i = 8.0 Hz, 2 H), 7.13 (d, I J i = 8.0 Hz, 2 H), 3.83 (t, I J i = 5.6 Hz, 2 H), 2.88-2.85 (m, 2 H), 2.32 (s, 3 H), 1.92 (s, 1 H). [Extracted from the article]

A reliable method for preparing P(III)‐arylphosphinecarboxamide derivatives from N‐arylphosphinecarboxamides and aryne precursors has been developed. This reaction was carried out without transition‐metal catalysts, and a series of unsymmetrically structured phosphinecarboxamide derivatives were obtained under mild conditions. In addition, the reaction is carried out under air atomosphere, and the corresponding P(III)‐aryl phosphinecarboxamide compounds are also stable in air. [ABSTRACT FROM AUTHOR]

This report describes the oxidative coupling reaction of dithiopyrimidines with phenylhydrazine hydrochlorides to synthesize a series of arylthiopyrimidine derivatives. The reaction does not require transition metals as catalysts, and uses organic dye rose bengal as photocatalyst and air as oxidant. The reaction conditions are mild and meet the requirements of green chemistry. In addition, the method has a wide scope of substrates and good tolerance of functional groups. The control experiment showed that the reaction may be a free radical mechanism, and the molecular weight of the intermediate was captured by high‐resolution mass spectrometry. [ABSTRACT FROM AUTHOR]

An efficient synthesis of C2-aryl pyrimidine derivatives via Pd-catalyzed Hiyama couplings has been developed. Various 2-chloro pyrimidines with electron-donating or electron-withdrawing groups as novel electrophile partners coupled well with trimethoxy(phenyl)silane and vinyltrimethoxysilane in the presence of CuCl and TBAF, providing desired products in good to excellent yields. This procedure showed good functional group tolerance, and the electronic and steric effects of 2-chloro pyrimidines seem to be negligible for the transformation. [ABSTRACT FROM AUTHOR]

N-doped porous carbon (NC) was synthesized from sugar cane bagasse, which is a sustainable and widely available biomass waste. The preferred NC sample had a well-developed porous structure, a graphene-like surface morphology and different N species. More importantly, the heterogeneous carbocatalyst exhibited superior catalytic performance in the aerobic dehydrogenation of various heterocyclic nitrogen compounds (49 examples, up to 96% yield), similar to that of C3N4 and GO. Characterization by TEM, BET and XPS accompanied by the EPR analysis revealed that the enhanced catalytic properties of NC came from its high activation ability for both O2 and heterocyclic nitrogen, attributed to the porous structure and pyridinic N (N-6) species, respectively. [ABSTRACT FROM AUTHOR]

An efficient palladium-catalyzed Hiyama reaction between various pyrimidin-2-yl tosylates with organosilanes has been developed. The use of CuCl with TBAF as additive is essential for promotion of the construction of the carbon–carbon bond. This procedure shows wide functional group tolerance for electrophilic pyrimidin-2-yl tosylates and has been extended to aromatic amino-substituted pyrimidin-2-yl tosylates, affording the desired C2-aryl and alkenyl pyrimidine derivatives in good to excellent yields. [ABSTRACT FROM AUTHOR]

This report describes the electrocatalytic regioselective acyloxylation and halogenation of aromatic C(sp2)‐H bond in an undivided cell without any toxic or expensive metals. This electrocatalytic acyoxylation of phenyl ether resulted in chemoselective C−H bond functionalization to give a series of aryl ether products with acyloxy, hydroxyl and halogen group. In addition, cyclic voltammograms showed that the electrode was the first step to oxidize aromatic rings, and a possible mechanism was proposed based on the experimental results. [ABSTRACT FROM AUTHOR]

A novel copper-nanoparticle-decorated sulfur-based polymer, Cu@S-co-BIM, was designed and constructed for the chronoamperometric analysis of glucose with high sensitivity and selectivity. S-co-BIM was synthesized via inverse vulcanization as a stable conductive substrate that displayed extraordinary electrical conductivity. Copper nanoparticles were electrodeposited as the catalyst. Combining abundant active sites and the high conductivity of S-co-BIM with the excellent electrocatalytic abilities of copper nanoparticles, the Cu@S-co-BIM sensor significantly increased the selectivity and sensitivity towards glucose determination. The amperometric current linearly increased with the glucose concentration in the range of 1 μM–3.3 mM, with a detection limit of 0.32 μM. The proposed sensor exhibited high selectivity to glucose oxidation in the presence of various interfering species, such as ascorbic acid (AA), uric acid (UA), sodium chloride, fructose, xylose, and maltose. The as-prepared sensor also exhibited excellent reproducibility and long-term stability. This new method was successfully applied for the detection of glucose in serum and in commercial gluconate oral liquid with satisfactory results. In addition, the proposed composite materials might provide a new strategy for expanding the applications of sulfur-rich polymers in the field of sensing. [ABSTRACT FROM AUTHOR]

Methods for the synthesis of 1,2,4-triazolidines are scarce. Herein, we report a visible-light-promoted decarboxylative addition cyclization of N-aryl glycines and azobenzenes to access such important compounds. Using commercially available methylene blue (MB) as an organic photocatalyst, the reaction proceeded smoothly in the absence of transition-metal catalysts at ambient temperature, affording the corresponding products, 1,2,4-triaryl 1,2,4-triazolidines, in good to excellent yields. This work demonstrates a new synthetic application of readily available azobenenes and provides a novel strategy for constructing 1,2,4-triazolidines. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: This paper describes the first case of a reductive coupling reaction with indene, a non‐heteroatom olefin used as a reducing agent. The scope of the substrate is wide. The homo‐coupling, cross‐coupling, and synthesis of 12 and 14‐membered rings were realized. The control experiment, indene‐product curve and density functional theory calculations showed that the η3‐palladium indene intermediate was formed by C—H activation in the presence of cesium carbonate. We speculate that the final product was obtained through a Pd (IV) intermediate or aryl ligand exchange. In addition, we excluded the formation of palladium anion (Pd(0)−) intermediates. [ABSTRACT FROM AUTHOR]

Herein, the sulfhydrylation and oxylation of olefins were completed under visible light irradiation with iodine as catalyst, which realized more economical and green chemical conversion because of the absence of metal complexes or organic dyes. A series of bifunctional modifications of olefins were achieved with good yields by using diol derivatives and water as nucleophiles. In addition, the control experiments show that the reaction is a free radical process. [ABSTRACT FROM AUTHOR]

Rhodamine B is a non-degradable carcinogenic dye, so it is of great significance to remove rhodamine B from wastewater. We designed and prepared a novel porous organic polymer adsorbent (DAPS-TP-POP), which contains abundant N, O, and S heteroatoms. DAPS-TP-POP was characterized through FT-IR, PXRD, TGA, TEM, BET etc. The results show that DAPS-TP-POP has high stability and abundant heteroatoms. DAPS-TP-POP has good adsorption capacity for rhodamine B. Besides, it also shows excellent recyclability. [ABSTRACT FROM AUTHOR]

A metal‐free C−P bond cleavage reaction is described herein. Phosphoramides, a phosphine source, can react with alcohols to produce phosphonate and phosphinate derivatives in the presence of a disulfide. P−H2, P‐alkyl, and P,P‐dialkyl phosphoramides can be used as substrates to obtain the corresponding pentavalent phosphine products. [ABSTRACT FROM AUTHOR]

A method for the electrochemical synthesis of sulfinic esters by aerobic oxidative coupling of thiophenols and alcohols has been developed. Using electrons as the redox reagent and O2 in air as the oxygen source, the reactions proceeded smoothly at room temperature, even for a gram-scale preparation. No use of catalyst, clean redox reagent, green and abundant oxygen source, and mild reaction conditions make this strategy eco-friendly. [ABSTRACT FROM AUTHOR]

An efficient desulfurization C–O coupling reaction of 3,4-dihydropyrimidine-2(1 H)-thiones (including thioureas) with alcohols was developed under electrochemical oxidation conditions. Herein, transition--metal catalysts and additives are not required and the alcohol is both the solvent and the alkoxy donor. [ABSTRACT FROM AUTHOR]

Herein, we report a non‐metal strategy for cyclization reactions of 2‐vinylanilines with/without isonitriles to synthesize 2‐aminoquinoline and 3‐aryl‐1H‐indole derivatives. A series of 2‐aminoquinolines were afforded in good to excellent yields in a direct, facile, and efficient approach by Se‐catalyzed isocyanide insertion with 2‐vinylanilines under an air atmosphere. This reaction not only used low toxicity Se as the catalyst, isocyanobenzene substrates were compatible too compared to previous report. Meanwhile, an intramolecular cyclization of 2‐vinylanilines was developed to give 3‐aryl‐1H‐indoles in moderate to good yields by using SeO2 as oxidant. [ABSTRACT FROM AUTHOR]

A recyclable and non‐phosphine solid palladium (II) catalyst was prepared and characterized by HR‐MS, FT‐IR, XPS, EDS, TGA, SEM, TEM and ICP. The Pd‐catalyst exhibited high‐performance catalytic activity in Suzuki and Heck C‐C coupling reactions in an environmentally benign water medium. Further, the Pd‐catalyst (Z4) can be reused for 15 times with little decrease of activity through simple and efficient recovery. In addition, the turn‐over number (TON) of Pd‐ catalyst can reach 380 at room temperature. These results proved that the Pd‐catalyst has a stable structure and can be recycled many times, making the process sustainable. [ABSTRACT FROM AUTHOR]

An efficient method for carbon–carbon bond formation is described. The process employs the palladium-catalyzed and copper-mediated cross-coupling of quinoline-2-(1 H)-thiones with arylboronic acids or alkynes through C–S bond cleavage without an inert atmosphere. The method provides rapid and general access to a diverse range of 2-substituted quinolines in a single step from a wide range of quinoline-2-(1 H)-thiones and arylboronic acids or alkynes. [ABSTRACT FROM AUTHOR]

An iodine promoted cascade cycloisomerization of 1-en-6,11-diynes is presented for the easy preparation of tetrahydrobenzo[f]isoquinolines. This developed reaction system is identified as having good functional-group applicability and can be scaled up to gram quantities. In this transformation, two new cyclic frameworks and one carbonyl group are formed with four new bonds constructed. Additionally, the resulting iodo-substituted compounds could be further derived through simple elimination reactions. [ABSTRACT FROM AUTHOR]

An efficient and halogen-free catalytic methodology for the synthesis of β-amino alcohols from aromatic amines and biomass-derived carbohydrates is demonstrated for the first time. The activation of C5/C6 sugars by a ruthenium catalyst selectively generates the C2 alkylating reagent glycolaldehyde. The transformation involves metal-catalyzed hydrogen borrowing for the reduction of the imine intermediate. A series of arylamines bearing various substituents were successfully transformed into the desired products in good to excellent yields. [ABSTRACT FROM AUTHOR]

A simple protocol for the UV light irradiated preparation of heteroaryl trifluoromethyl thioethers from disulfides and inexpensive, environmentally sodium triflinate (CF3SO2Na) has been developed. The features of simple and clean reaction conditions, in moderate to good yields, and broad substrate scope render this new approach synthetically attractive for the preparation of potentially pharmaceutically active compounds. A trifluoromethylation of diheteroaryl disulfides with CF3SO2Na to afford the trifluoromethyl thioethers derivatives. The conversion has good functional group compatibility, without external photocatalyst, generating the corresponding products in moderate to good yields under mild conditions, and the disulfide is fully utilized while constructing two S‐CF3 bonds. [ABSTRACT FROM AUTHOR]

An electrochemical method to achieve carbamoylphosphonates from phosphoramides and alcohols via P–H oxidation and functionalization by using n-Bu4NI as a catalyst is reported. A series of carbamoylphosphonates were obtained with good to excellent yields under mild reaction conditions. The electrochemical reaction is carried out under constant current electrolysis, with the alcohol being used as a solvent and a substrate, and is an attractive green synthesis method. [ABSTRACT FROM AUTHOR]

Abstract: Organic phosphonates and their derivatives are an important class of compounds in a variety of fields, especially medicinal chemistry, materials chemistry, agrochemistry and catalysis. For example, phosphonate esters and carbamoylphosphonates are matrix metalloproteinase (MMP) inhibitors, antimetastatic agents and antitumor agents. Phosphonate esters are usually prepared via a multistep transformation from a phenol and an organohalide and require toxic phosphorus halides and aryl/alkyl halides. , Palladium‐catalyzed couplings of an aryl halide (ArX) with a P−H compound, which were developed by Hirao and co‐workers, are now typically used as efficient and substrate‐tolerant methods for preparing phosphonates (Scheme 1). , Recently, great advances were made in the synthesis of phosphonate esters via metal‐catalyzed C−P bonds couplings of H‐phosphonates with C−X compounds (X=B, N, O, S and Si). Despite these clear advances, metal‐catalyzed coupling reactions of P−H with C−X(H) are still limited by the need for costly noble metal catalysts. [ABSTRACT FROM AUTHOR]

Here, we report a base-controlled chemo-selective reaction of vinylanilines with alkyl/aryl isothiocyanates to afford quinolino-2-thione and 2-aminoquinoline derivatives. The quinolino-2-thiones could be obtained in high yields in the presence of Et3N. Particularly interesting is that the reaction could produce the 2-aminoquinolines in the presence of K3PO4 with high selectivity. [ABSTRACT FROM AUTHOR]

The Pd‐catalyzed cross‐coupling reaction of 1, 2‐di(pyrimidin‐2‐yl) disulfides with heterocyclic amines including 2‐amino pyrimidines and 1,3,4‐thiadiazol‐2‐amines to deliver symmetrical C‐N coupling products in moderate to good yields is reported. This method provides an opportunity for synthesis of bioactive molecules and pharmaceutically interesting compounds containing heterocycle motifs. The reported protocol shows good functional group compatibility, and provides a new strategy for preparation of C2‐amination pyrimidine derivatives from heterocyclic disulfides. [ABSTRACT FROM AUTHOR]

Here we show that the base-catalyzed thio-lactamization of 2-(1-arylvinyl)anilines with CS2 is a powerful methodology to synthesize quinoline-2-thiones. This thio-lactamization uses inexpensive and versatile 2-(1-arylvinyl)anilines, which are easily available from the reaction of amines and alkynes. Compared to the known strategy in the literature, this method features the advantages like a short synthesis step and easily available starting materials. [ABSTRACT FROM AUTHOR]

Abstract: An amine‐methylchloroformate‐paraformaldehyde‐styrene condensation catalyzed by aluminium(III) triflate is described, leading to the synthesis of allylamides. This condensation provides an efficient method for the N‐carbonylation and N‐allylation of various aliphatic primary amines in good to excellent yields. [ABSTRACT FROM AUTHOR]

The reaction of the 2-phosphaethynolate anion and primary amines for the mechanochemical synthesis of phosphinecarboxamides was studied. The reaction has its own merits, such as rapid reaction rate, high yield, mild and acid-free conditions. The mechanochemical strategy offers a solvent-free reaction environment with real-time monitoring of the parameters, optimizing the reaction conditions and studying the mechanism without requiring further workup. The mechanism was investigated with use of IR, 13C NMR, and 31P NMR spectroscopy. [ABSTRACT FROM AUTHOR]

Glycerol is a new green organic solvent. It not only acts as a phase transfer catalyst but also as a recyclable solvent by significantly enhancing the intramolecular cyclization. A series of 4-aryl-7,7 -dimethyl-5-oxo-3,4,5,6,7,8-hexahydrocoumarin derivatives were synthesized by one-pot multicomponent reaction of Meldrum’s acid with benzaldehyde, and cyclohexanedione in glycerol. Compared to classic methods, this method has the advantages of milder reaction conditions, good yields, easy processing and environmental benignity. [ABSTRACT FROM AUTHOR]

The straightforward visible-light-induced synthesis of stilbene compounds via the cross-coupling of nitroalkenes and diazonium tetrafluoroborates under transition-metal-free conditions is described. The protocol uses green LEDs as light sources and eosin Y as an organophotoredox catalyst. Broad substrate scope and exclusive selectivity for the (E)-configuration of stilbenes are observed. This protocol proceeds via a radical pathway, with nitroalkenes serving as the radical acceptor, and the nitro group is cleaved during the process. [ABSTRACT FROM AUTHOR]

Nickel-catalyzed of pyrimidin-2-yl tosylates with indole and benzimidazole was achieved using Ni(dppp)Cl2 as catalyst, yielding a variety of novel C2-substituted pyrimidine derivatives in good yields. This reaction proved to be tolerant of various pyrimidin-2-yl tosylates bearing either electron-donating or electron-withdrawing groups as well as nucleophiles including indole, benzimidazole and 1,2,4-triazole. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A simple and practical denitrated coupling reaction of nitroalkenes with various alkenes using a nickel catalyst and triethoxysilane [(EtO)3SiH] as reducing agent was achieved. Under mild reaction conditions, both aliphatic and aromatic alkenes could react with nitroalkenes to obtain a series of olefins with different functional groups in satisfactory yields under an air atmosphere, which were previously difficult or impossible to access. [ABSTRACT FROM AUTHOR]

The allylamine skeleton represents a significant class of biologically active nitrogen compounds that are found in various natural products and drugs with well-recognized pharmacological properties. In this personal account, we will briefly discuss the synthesis of allylamine skeletons. We will focus on showing a general protocol for Lewis acid-catalyzed N-allylation of electron-poor N-heterocyclic amides and sulfonamide via an amide-aldehyde-alkene condensation reaction. The substrate scope with respect to N-heterocyclic amides, aldehydes, and alkenes will be discussed. This method is also capable of preparing the Naftifine motif from N-methyl-1-naphthamide or methyl (naphthalene-1-ylmethyl)carbamate, with paraformaldehyde and styrene in a one-pot manner. [ABSTRACT FROM AUTHOR]

Pyrimidin-2-yl sulfonate, as an efficient reaction partner, can be easily prepared from cheap commercial materials, reacted with sodium azide and alkynes to give C2-triazolo functionalized pyrimidines in good yields under mild reaction conditions. This procedure eliminates the need to handle organic halides or organic azides, as they are generated in situ, making this already powerful click process even more user-friendly and safe. [ABSTRACT FROM AUTHOR]

Iron-catalyzed Kumada cross-coupling reactions of pyrimidin-2-yl phosphates and Grignard reagents are described. The reaction proceeds at room temperature with a short reaction time of 15 minutes, and the corresponding products are obtained with moderate to high yields. A wide array of C2-functionalized pyrimidines has been prepared in moderate to good yields and many functional groups are well tolerated. [ABSTRACT FROM AUTHOR]