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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]

Abstract We report a rhodium-catalyzed ortho C(sp 2)-H borylation of 2-phenylpyridines using commercially available N-heterocyclic carbenes (NHCs) as ligand and pinacolatodiboron (B 2 pin 2) as borylating reagent. The reaction could take place at room temperature, tolerating a wide range of functionalities and affording ortho borylated products in moderate to excellent yields. The current method is also applicable to gram-scale reaction with reduced catalyst loading. Graphical abstract Image 3 [ABSTRACT FROM AUTHOR]

Review: [26 refs. [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]

The approach to the synthetically important target compounds is simple, cost-efficient and environmentally friendly. [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]

Pyrimidin-2-yl tosylates which are successfully applied as the electrophiles instead of halides coupled with olefins via Pd(PPh 3 ) 2 Cl 2 catalyzed Mizoroki–Heck reaction conditions to give the corresponding C2-alkenyl pyrimidine derivatives with high β -regioselectivity. This protocol proves to be tolerant of various pyrimidin-2-yl tosylates as well as various olefins including styrene derivatives, aliphatic olefins (vinyl cyanide, methyl acrylate, ethyl acrylate, n -butyl acrylate, butyl vinyl ether, 1-hexene and 1-octene). [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]

Abstract: A simple and highly selective colorimetric sensor (L1) bearing thiosemicarbazide moiety as binding site and nitrophenyl moiety as signal group were synthesized. Sensor L1 showed great colorimetric single selectivity and high sensitivity for mercury cation in DMSO and DMSO/H2O binary solutions. When Hg2+ was added to the DMSO solution of L1, dramatic color change from brown to colorless was observed. While the cations Ca2+, Mg2+, Cd2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Pb2+, Ag+ and Cr3+ could not cause any distinct interferer toward the recognition process for Hg2+. The detection limit is allowable to 5.0×10−6 and 1.0×10−7 M level of Hg2+ according to visual color change and UV–vis change, respectively. The recognition mechanism of the sensor toward mercury cation was evaluated in DMSO solutions by UV–vis and 1H NMR. The sensor selectively sense Hg2+ via the formation of a stable 1:1 complex through Ce:glyph name="dbnd" />O group with Hg2+. When these complex bonds formed, the sensor carried out an ICT transition induced color change. [Copyright &y& Elsevier]

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]

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]

[Display omitted] • Inverse vulcanisation by photopolymerisation in solvent systems. • Allows solid crosslinkers, such as β-carotene, to react at RT. • Widely transferrable across liquid, volatile and even gaseous systems. • Prevents the production of the toxic H 2 S by-product; • Crucial role of trace water in IV reaction under thermal conditions. Inverse Vulcanisation (IV) under neat reaction conditions (without solvent) has enabled the research and development of the fundamental chemistry as well as the generation of unique sulfur-rich polymers with unprecedented properties. However, such bulk polymerisation can be problematic, especially with high molecular weight. The energetics of the thermal polymerisation process, combined with poor heat control of solvent-free polymerisation, cause risks of dangerous auto-acceleration if the process is scaled up. The required high temperatures (>160 °C or 135 °C even with catalysts), exceed the boiling point of most commonplace organic solvents, preventing implementation of solvents for IV under thermal conditions. We report here a photo-induced IV polymerisation in solvent at room temperature. The reactions proceed smoothly and efficiently with excellent yields, despite the potential negative factors of reflection, refraction, and low absorption intensity of light by these organic solvents, opening an attractive avenue for the preparation of functional sulfur-rich polymers as well as their potential applications. The extension of crosslinkers to the value-added C5 fraction of industrial byproduct and β-carotene showcase the benefit of this low temperature protocol. Mechanistic study reveals that the moisture in both substrates and solvents might play a key role for the generation of toxic H 2 S by-product in IV reaction under thermal conditions, with photopolymerisation remaining un-affected. This protocol not only extensively expands the scope of crosslinkers for the IV reaction together with resultant polymers, but also provides a potential scale-up route for industrial application by avoiding the generation of toxic H 2 S by-product and possible explosion risk with high temperature. [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]

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]

• Direct allylation of chiral oxazolidinone with aldehydes and olefins. • I 2 -catalyzed amide-aldehyde-olefin condensation. • From inexpensive and abundant un-activated olefins. An iodine-catalyzed direct allylation of chiral oxazolidinones with aldehydes and alkenes has been developed. The reaction proceeds, without use of any bases or metals, directly converted the 3-chiral oxazolidinones into N -allylated oxazolidinones. Additionally, the 3-chiral allylamine skeleton was constructed and the diastereomers were isolated by simple column chromatography. [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]

Abstract KMnO 4 -mediated oxidative C N bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields. Graphical abstract Image 1 [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]

Graphical abstract Highlights • Methylation of quinoline-2-thione under mild and environmentally friendly conditions. • DMSO as readily available source of methyl group. • Using UV light without metal- and dye-photocatalyst. Abstract An UV-light-induced S- methylation of quinoline-2-thione was completed by using dimethyl sulfoxide as methyl reagent. A series of quinoline methyl sulfides were prepared in moderate to good yields under environmentally friendly and mild conditions. [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]