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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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

An Fe(III)-catalyzed of N-heteroaromatic tosylates with aryl and alkyl Grignard reagents is presented. The reaction proceeds at −20°C to room temperature with short reaction time (15-30 min.), and the corresponding products are obtained with moderate to high yields. In particular, low-cost and abundantly available FeCl3 or Fe(acetylacetonate)3 catalyze the reaction without other special ligands. All tested N-heteroaromatic tosylates that are available including pyridine and pyrimidine derivatives were subject to the reaction, resulting in the expected products. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A general protocol for the chemoselectivity-controlled CC and CS coupling reactions of di(hetero)aryl disulfides with Grignard reagents catalyzed by ferrocene and palladium acetate has been developed. Ferrocene favored the formation of CS coupled products at low temperature, whereas CC bond couplings were favored when palladium acetate was used. All the reactions proceeded with excellent chemoselectivity and in good yields under mild conditions, and a library of molecules with pyridine and pyrimidine scaffolds was produced. [ABSTRACT FROM AUTHOR]

We report a general protocol for the direct N-allylation of electron-poor N-heterocyclic amides and sulfonamides via an amide-aldehyde-alkene condensation reaction catalyzed by a Lewis acid. This process has a broad substrate scope with respect to N-heterocyclic amides including carbamates, carboxamides, and N-methylsulfonamides, and provides efficient access to a variety of allylamine derivatives in good yield with high regioselectivity. The utility of this method was also demonstrated by the rapid synthesis of Naftifine from N-methyl-1-naphthamide, paraformaldehyde, and styrene in one-pot. [ABSTRACT FROM AUTHOR]

An efficient method for carbon-carbon bond formation is described. The process employs the palladium-catalyzed copper-mediated cross-coupling of diheteroaryl disulfides with arylboronic acids or alkynes to deliver CC coupling products through unreactive CS bond cleavage. The scope of the coupling reactions, including both the disulfides and arylboronic acids or alkynes, are documented. [ABSTRACT FROM AUTHOR]

of amides and anilines with aryl iodides was efficiently catalyzed by copper thiophenecarboxylate under ligand-free conditions with good to excellent yields. A variety of substituted aryl iodides, amides, anilines and 4-aminoantipyrine were found to be applicable to the simple catalytic system. Furthermore, some practical, unique secondary amides, such as N-arylacrylamides and 4-amido- N-phenylbenzamides, and 4-amino( N-phenyl)antipyrenes, which are difficult to obtain by the classical methods, were prepared. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Pyrimidin-2-yl sulfonates, as a reaction partner, can be easily prepared from inexpensive commercial materials and are efficiently cross-coupled with arylboronic acids and terminal alkynes by using Pd(OAc)2-catalyzed Suzuki and Sonogashira reactions. A wide array of C2-functionalized pyrimidines have been prepared in good to excellent yields. 2-Arylpyridines and 2-(oct-1-ynyl)pyridine were also synthesized. [ABSTRACT FROM AUTHOR]

The molecular iodine-catalyzed three-component reaction of amides or amide derivatives, paraformaldehyde and styrenes allows for the clean generation of allylamine derivatives in good yields and high regioselectivities. The reaction, forming water as the sole co-product, is an experimentally easy to conduct transformation in the absence of transition metals under mild conditions. [ABSTRACT FROM AUTHOR]

A domino desulfitative coupling/acylation/hydration process to synthesize C-2-(2-oxo-2-phenylethylidene)- and N-3-carbonyl-substituted pyrimidines by unprecedented CC and CN cross-coupling reactions is described. This methodology couples 3,4-dihydropyrimidine-2-thiones and alkynes under modified Liebeskind-Srogl conditions using palladium acetate and copper(I) carboxylate. Remarkably the copper(I) carboxylates simultaneously act as desulfitative and acylation reagents in the reaction. [ABSTRACT FROM AUTHOR]

Review: [26 refs. [ABSTRACT FROM AUTHOR]