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A palladium-catalysed Hiyama cross-coupling reaction of alkynyl halides with aryltrialkoxysilanes has been developed. Catalysed by bis(dibenzylideneacetone)palladium and in the presence of silver fluoride and potassium bicarbonate, a variety of alkynyl halides (I, Br and Cl), whether electron-deficient or electron-rich, underwent the cross-coupling reaction with aryltrialkoxysilanes at room temperature to afford the corresponding alkynes in moderate to good yields. [ABSTRACT FROM AUTHOR]

The paper reported the catalysis of simple μ-oxo dimeric metalloporphyrins for the selective oxidation of ethylbenzene with air under mild conditions in the absence of additives. Two simple μ-oxo dimeric metalloporphyrins, μ-oxo-bis(tetraphenylporphinato)iron [TPPFe]2O and μ-oxo-bis(tetraphenylporphinato)manganese [TPPMn]2O were used as catalyst in the oxidation of ethylbenzene with air under mild condition. The results show that the products of ethylbenzene oxidation catalyzed by [TPPFe]2O or [TPPMn]2O with air are acetophenone and α-phenylethanol exclusively under T>60 °C and atmospheric pressure and in absence of any additive. [TPPMn]2O is an active catalyst with high selectivity and turnover number of 2134 for oxidation of ethylbenzene by air when temperature reacts at 70 °C. The kinetic study shows that the ethylbenzene oxidation is zero-order for oxygen and first-order for ethylbenzene. The activation energy of the reaction is 72.7 kJ/mol. Comparing with the corresponding monometalloporphyrins TPPFeCl and TPPMnCl, [TPPFe]2O and [TPPMn]2O have the better catalytic activity for ethylbenzene oxidation with air without any additive under mild conditions. [Copyright &y& Elsevier]

A Brønsted acid Ph2P(O)OH can efficiently catalyze the reaction of a Pd(0) complex with an alkyne to produce a novel alkenyl(alkynyl)palladium complex via selective hydropalladation and ligand exchange processes. On the basis of this finding, an efficient Pd(0)/Ph2P(O)OH mediated head-to-tail dimerization of alkynes was disclosed. [ABSTRACT FROM AUTHOR]

Alkynyl iodide [e.g. (Ic)] is not suited as starting material since homocoupling occurs as side process. [ABSTRACT FROM AUTHOR]

A highly selective head-to-tail dimerization of aliphatic and aromatic alkynes (I) and (III) is reported. [ABSTRACT FROM AUTHOR]

There is significant interest in developing new catalyst supports such as metal carbides to overcome the electrochemical corrosion problem of traditional high surface area carbon. A key challenge is the dispersion and stability of the catalysts on the non-carbon based materials. This paper reports a new approach to functionalize titanium carbide by poly (diallyldimethylammonium chloride) (PDDA), investigated as a new catalyst support for Pd catalyzed electrochemical reaction. Thermal gravimetric analysis confirmed the successful noncovalent functionalization of TiC by PDDA. Pd nanoparticles are deposited in situ on the PDDA-wrapped TiC surface through electrostatic interactions mechanism. According to transmission electron microscopy (TEM) observations, Pd nanoparticles with a mean size of ∼2.9 nm are homogeneously deposited on TiC(P). Among all the samples tested, the Pd/TiC(P) catalysts exhibit the highest resistance to CO poisoning, catalytic activity and stability towards formic acid electrooxidation. This performance was attributed to a strong Pd↔TiC interaction and the formation of oxygenated species on the TiC. [ABSTRACT FROM AUTHOR]

A one‐step protocol is described for the synthesis of arylacetaldehydes from aryl aldehydes or diaryl ketones by using the system of DMSO/KOH/zinc. In this transformation, DMSO provides a methine fragment that converts the −CHO structure in aryl aldehydes or the −CO− structure in diaryl ketones to the −CH2CHO structure in arylacetaldehydes via a one‐carbon extension. This protocol could also be used to synthesize arylacetaldehyde acetals from aryl aldehydes or diaryl ketones when zinc was replaced by diols. In this protocol, 25 examples of arylacetaldehydes and 26 examples of arylacetaldehyde acetals have been synthesized from aryl aldehydes or diaryl ketones. Based on control experiments and the literature, a plausible reaction mechanism is proposed in our work. [ABSTRACT FROM AUTHOR]

A transition‐metal‐free protocol for the synthesis of non‐terminal alkenyl ethers, alkenyl sulfides, and N‐vinylazoles from arylaldehydes or diarylketones, DMSO and O, S, N‐nucleophiles has been reported. In this protocol, 24 examples of non‐terminal alkenyl ethers and 28 examples of non‐terminal alkenyl sulfides in 72–95% yields have been synthesized within 5 min. Moreover, 27 examples of non‐terminal N‐vinylazoles with 57–88% yields have also been synthesized within 2 hours. The preliminary mechanism investigations revealed that arylaldehydes or diarylketones offered a carbon atom, DMSO provided a methine and O, S, N‐nucleophiles contributed one X atom for constructing C=C−X structure. [ABSTRACT FROM AUTHOR]

Non-transition metal-catalyzed synthesis of phenacyl bromides was achieved through K2S2O8-mediated tandem hydroxybromination and oxidation of styrenes. The advantages of this reaction are its excellent functional group compatibility, mild reaction conditions (60 °C) and use of pure water as reaction medium. Based upon experimental observations, a plausible reaction mechanism is proposed. [ABSTRACT FROM AUTHOR]

A protocol for the synthesis of terminal N‐vinylazoles from aromatic aldehydes, DMSO, and azoles has been reported. In this strategy, DMSO was involved in the construction of the C=C bond as a terminal carbon synthon. Both aromatic aldehydes and azoles could be well tolerated and give the corresponding terminal N‐vinylazoles in 52–91% yields. Based on preliminary experiments, a plausible mechanism is proposed. [ABSTRACT FROM AUTHOR]

A [3+1+1+1] cycloaddition was developed among 2‐arylpropene, ketone and DMSO in the presence of K2S2O8. 2‐arylpropene provides three carbons, ketone offers one carbon, and DMSO as dual carbon donor contributes two carbons to the six‐membered carbocycle. It gave the cyclohexene motif and spirocyclohexene skeleton. Four C−C bonds formed in this process. Both propylene and ketone could be well tolerated and give the corresponding cyclohexene or spirocyclohexene motif in useful yields. Based on the controlled experiments, a possible mechanism was proposed. [ABSTRACT FROM AUTHOR]

A new [3+2+1] annulation strategy based on the heteroatom‐free tri‐atom donor to synthesize 3,6‐dihydro‐2H‐pyrans has been developed. In this method, 2‐arylpropylene served as tri‐atom donor to contribute three carbon atoms, the heteroatom was provided by aldehyde, and DMSO served as one carbon donor and solvent. This annulation reaction gave 3,6‐dihydro‐2H‐pyrans in moderate to good yields. Based on the control experiments, a possible mechanism was proposed. [ABSTRACT FROM AUTHOR]

A copper acetate‐mediated reaction of benzaldehydes with nitromethane to synthesis of 3‐nitroisoxazoles is reported. A variety of nitro‐aryl‐disubstituted isoxazole derivatives can be prepared in moderate to good yields with benign functional group tolerance. This protocol is successfully applied in gram‐scale reaction. Preliminary mechanistic studies reveal that the aldehyde provided one carbon atom for the isoxazole ring, and nitromethane provided two carbon atoms and one nitrogen atom for the isoxazole ring. In this protocol, the C−O−N unit in the final isoxazole ring is formed from the rearrangement of nitromethane. [ABSTRACT FROM AUTHOR]

A convenient synthetic approach for the synthesis of α‐oxo‐acetamidines via copper‐catalyzed C(sp3)‐H amidination has been developed. This approach allows the direct amidination of three C(sp3)‐H bonds without cyclization.Methyl ketones and primary and secondary amines are tolerant and afford the corresponding products in moderate to good yields. Furthermore, this protocol is also applicable to the synthesis of unsymmetrical α‐oxo‐acetamidines via one‐pot, multicomponent reactions (MCRs). [ABSTRACT FROM AUTHOR]

An efficient protocol for the synthesis of substituted oxazoles via an annulation of ketones, DMSO, and ammonium is reported. DMSO is first found to serve as oxygen donor in annulation resulting in regioselective synthesis of 2,4‐disubstituted oxazoles. With the optimized conditions in hand, 22 examples of 2,4‐disubstituted oxazoles are obtained from readily available substrates. The protocol can be also applied in cross‐condensation reactions between methyl ketones and non‐methyl ketones resulting 4 examples of 2,4,5‐trisubstituted oxazoles. Moreover, we have successfully applied the protocol into gram‐scale representing good yields, that showing the potential practicality in organic synthesis. Based on control experiments and literature, a plausible reaction mechanism was proposed in our work. [ABSTRACT FROM AUTHOR]

An unusual I2‐mediated triple C(sp3)−H functionalization reaction between aryl methyl ketones and dimethyl sulfoxide to form polysubstituted furans has been developed. In this transformation, dimethyl sulfoxide functions as a dual synthon via C(sp3)−H functionalization with formation of two C−C bonds, one C−O bond, and one C−S bond in a one‐step process. Iodine is crucial as promoter of the reaction, by which a number of ketones could be converted easily into 2,4,5‐trisubstituted furans. This provides an extremely simple and expeditious approach to high‐value‐added, biologically significant O‐heterocycles. Based on preliminary experiments, a plausible mechanism is proposed. [ABSTRACT FROM AUTHOR]

Abstract: A Cu‐catalyzed C−H cyclization of simple anilines with ketones and DMSO as a one‐carbon source has been developed. Using an aerobic oxidative protocol, a number of ketones and anilines could be easily converted to 2‐arylquinolines, rather than 4‐arylquinolines, thus providing a highly atom‐economical and simple approach to biologically significant 2‐arylquinolines. Based on the preliminary experiments, a plausible mechanism is proposed. [ABSTRACT FROM AUTHOR]

A bio-inspired approach for efficient conversion of cellulose to formic acid ( FA) was developed in an aqueous alkaline medium. Metalloporphyrins mimicking cytochrome P450 exhibit efficiently and selectively catalytic performance in catalytic conversion of cellulose. High yield of FA about 63.7% was obtained by using sulfonated iron( III) porphyrin as the catalyst and O2 as the oxidant. Iron( III)-peroxo species, TSPPFeIIIOO−, was involved to cleave the C-C bonds of gluconic acid to FA in this catalytic system. This approach used relatively high concentration of cellulose and ppm concentration of catalyst. This work may provide a bio-inspired route to efficient conversion of cellulose to FA. [ABSTRACT FROM AUTHOR]

A coupling of multiple C(sp3)–H bonds of the methyl group in methyl ketones with dimethyl sulfoxide is developed. This coupling allows the direct C(sp3)–H bond coupling among three methyl groups and affords one C–C bond and one C=C bond under transition metal-free conditions. The value-added cyclized 3-methylthiomethyl chroman-4-ones can be synthesized through this method. A plausible mechanism is proposed. [ABSTRACT FROM AUTHOR]

The transformation of the C C bond of olefin to nitriles has been developed, using easily available NaNO 2 as both the nitrogen source and oxidant. Several aryl, heterocyclic nitriles with various substituting groups could be successfully prepared in good to high yields. Based upon experimental observations, a possible reaction mechanism is proposed. [ABSTRACT FROM AUTHOR]

A transition-metal-free nitration of alkenes with NaNO 2 in the presence of K 2 S 2 O 8 and 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) is developed. The transformation exhibits a broad substrate scope and good functional group tolerance, thus providing a new and expedient protocol for stereoselective synthesis of ( E )-nitroalkenes with moderate to good yields. Moreover, the nitration processes of ( E )- and ( Z )-stilbene are also studied: even though the proportion of substrates is different, the E / Z ratio of the products is basically the same. Based upon experimental observations, a possible reaction mechanism is proposed. [ABSTRACT FROM AUTHOR]

A silver-catalyzed highly efficient and regioselective synthesis of ketones from a wide range of alkynes is described. The reaction is dramatically accelerated by its performance in aqueous emulsion, which is self-assembled by the addition of silver perfluorooctanesulfonate ( 1 ) and perfluorooctanesulfonic acid (PFOS) to water. The reaction is conducted under convenient conditions with broad substrate scope, including a variety of aromatic and aliphatic terminal alkynes and internal alkynes. Furthermore, the air- and light-stable silver catalytic microemulsion can be reused for 4 times with minimal change in catalytic efficiency. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Iodine(III)-Mediated C-H Alkoxylation of Aniline Derivatives with Alcohols under Metal-Free Conditions," published in the "Journal of Organic Chemistry" in 2014.

The immobilized catalyst can be easily recovered from the reaction mixture via simple centrifugal separation and reused several times without severe deactivation. [ABSTRACT FROM AUTHOR]

The conversion of the C=O bond of ketones to a C≡N bond is described. This conversion is catalyzed by copper salts with ammonium salts as the nitrogen source in the presence of molecular oxygen. A wide variety of ketones can be converted into the corresponding compounds containing a C≡N bond. Based on the preliminary experiments, a plausible mechanism of this transformation is disclosed. [ABSTRACT FROM AUTHOR]

In order to improve the cathodic current efficiency of electroplating for nickel on graphite powders, the influence of temperatures and current densities on the cathodic current efficiency was studied. Meanwhile, the effects of composition in the plating solution were investigated through polarization curves of plating solution. The results showed that the optimal cathodic current efficiency occurred with an electrode area ratio of 1.0 between the anode and cathode at a current density of −9...−12 A dm at 55°C. Nickel coated graphite (Ni/graphite) powders with 60 wt % nickel were produced by electrodeposition for 30 min under the intermittent stirring. The characterization results of powders with SEM and EDS exhibited that high nickel coverage and uniform plating coating Ni/graphite powders were fabricated. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the synthesis of phenacyl bromides through potassium persulfate-mediated tandem hydroxybromination along with the oxidation of styrenes in the presence of water published in the journal "Green Chemistry" in 2013.

Review: 119 refs. [ABSTRACT FROM AUTHOR]

Highlights: [•] Metalloporphyrins were effective for the aerobic oxidation of 2-methoxy-4-methylphenol. [•] Various reaction parameters were systematically investigated. [•] Catalysis under mild conditions. [•] A possible reaction mechanism was proposed. [Copyright &y& Elsevier]

The first example of the cobalt-porphyrin-catalyzed aerobic oxidative coupling of phenols through oxidative C-H functionalization has been developed. In the presence of T( p-OMe)PPCo and Na2CO3, the oxidative coupling of phenols with different substituents proceeded smoothly with O2 as a terminal oxidant to give the corresponding biaryl compounds in satisfactory yields. The biaryl derivatives are important in the area of pharmaceuticals and as ligands in metal catalysis. Preliminary mechanistic studies of this oxidative coupling reaction are also reported. [ABSTRACT FROM AUTHOR]

Abstract: A series of C5-substituted licofelone ([2,2-dimethyl-6-(4-chlorophenyl)-7-phenyl-2,3-dihydro-1H-pyrrolizin-5-yl]acetic acid) derivatives were developed by a parallel synthesis approach and investigated for cytotoxicity against MCF-7 and MDA-MB-231 cells as well as for anti-inflammatory potency in vitro and in vivo. Dependent on the C5-substituent, the compounds showed high selectivity for MCF-7 cells. Especially 2-oxoethyl benzoate derivatives were inactive at the MDA-MB-231 cell line and as active as 5-FU at MCF-7 cells. C5-acetyl (8a), –2-oxoethyl formiate (8e), –2-oxoethyl acetate (8f) and –2-oxoethyl propionate (8g) derivatives showed growth inhibition at both cell lines, comparable with cisplatin. Modifications significantly reduced the inhibitory potency at COX-1 and COX-2 in vitro and in the xylene-induced ear swelling assay in mice. Only compound 8a was equipotent to licofelone, ibuprofen and celecoxibe in vivo. [Copyright &y& Elsevier]

Abstract: A stannylene acetal, in the presence of CsF, is able to cleave both aromatic and aliphatic acetates rapidly and efficiently under room temperature. Control experiments indicate that both the stannylene acetal and CsF are required and play significant roles in the deacetylation process. Thus, it is likely that the tin-based alkoxide anion generated by a stannylene acetal and CsF is responsible for deacetylation. [Copyright &y& Elsevier]

In the presence of iodobenzene diacetate with potassium iodide, aromaticα-phenoxy ketones underwent α-acetoxylation to afford corresponding α-acetoxy ketones smoothly at room temperature in moderate to good yields. [ABSTRACT FROM AUTHOR]

Abstract: Four novel porphyrins containing nitric oxide (NO) donors were synthesized, and the structures of all the products were characterized by IR, UV–vis, 1H NMR, and elementary analysis. Interestingly, these new compounds not only were able to release NO, but also showed cancer cell-oriented accumulation. Higher accumulation of these new porphyrins containing NO donors in BEL-7402 liver cancer cells than in L-02 liver normal cells was corroborated by UV–vis spectroscopy. The biological activity of these porphyrins against BEL-7402 liver cancer cells was tested with a MTT assay. The studies indicated that they had more effective killing of BEL-7402 liver cancer cells than that of L-02 liver normal cells, and they had similar activity against MCF-7 breast cancer cells when compared to 5-fluorouracil in the absence of light. [Copyright &y& Elsevier]

A variety of styrenes undergo nitrogenation reaction to afford the corresponding nitriles in high yields, whereas the reaction of internal alkenes (III) and (IV) proceeds sluggishly even under the optimized conditions. [ABSTRACT FROM AUTHOR]

An abstract of the article "K2S2O8-Mediated Nitration of Alkenes with NaNO2 and 2,2,6,6-Tetramethylpiperidine- 1-oxyl: Stereoselective Synthesis of (E)-Nitroalkenes" by An Zhaois, et al. is presented.

The selective oxidative halogenation of C-H bonds on porphyrins by halides/H2O2 is achieved. [ABSTRACT FROM AUTHOR]

An abstract of the article "Copper-Catalyzed Aerobic Conversion of the C=O Bond of Ketones to a C=N Bond Using Ammonium Salts as the Nitrogen Source" by Bin Xu and colleagues is presented.

A simple and metal-free direct cyanoisopropylation/arylation of N-arylacrylamides and N-alkyl-N-(arylsulfonyl)acrylamides with AIBN is developed using MeNO2 as both solvent and oxidant. [ABSTRACT FROM AUTHOR]

A diagram is presented on the amination of ketones through radical mechanism.

The article presents chemical equations related to the article "PIFA-Mediated Esterification Reaction of Alkynes with Alcohols via Oxidative Cleavage of Carbon Triple Bonds" by Q. Jiang and others, published in the periodical "Journal of Organic Chemistry" in 2014.

The article presents chemical diagram for the study which focuses on cobalt(II)-porphyrin-catalyzed aerobic oxidation of phenols.