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[Display omitted] • A new palladium-catalyzed redox-neutral dicarbonylation of terminal alkynes has been reported. • Hydroxylamine acts as both a nucleophile and a potential oxidant. • Maleimides were synthesized in moderate yields under relatively mild conditions. • A new idea for oxidative carbonylation reactions. A palladium-catalyzed redox-neutral dicarbonylation of terminal alkynes has been reported, in which hydroxylamine acts as both a nucleophile and a potential oxidant. Maleimides were synthesized in moderate yields under relatively mild conditions while avoiding the addition of equivalent oxidants. This reaction process involves two key steps: the addition of Pd-H to the terminal alkyne, and the hydroxylamine ester intermediate play the role of an internal oxidant via nucleophilic attack by hydroxylamine. This reaction has a wide range of functional group compatibility, and this internal oxidation reaction process also provided a new idea for other oxidative carbonylation reactions. [ABSTRACT FROM AUTHOR]

Transition‐metal‐catalyzed multicomponent carbonylation is one of the most efficient strategies to construct carbonyl‐containing compounds. Herein, a palladium‐catalyzed four‐component perfluoroalkylation/aminocarbonylation of unactivated alkenes with perfluoroalkyl halides, and amines was developed. A wide range of substrates, including anilines, alkylamines, sulfonamides, and hydrazines are all suitable reaction partners for this catalyst system, resulting in various β‐perfluoroalkyl amides with good functional‐group tolerance and excellent chemoselectivity. Furthermore, not only alkyl olefins, but also aliphatic alkynes, and even alkyl allenes can all be employed. Notably, several medical and bioactive related molecules are compatible here as well. [ABSTRACT FROM AUTHOR]

A palladium‐catalyzed carbonylative cyclization of propargyl amines and acid chlorides has been developed for the construction of 1,5‐dihydro‐2H‐pyrrol‐2‐one scaffolds. By employing TFBen as the CO source, the reaction provides a facile approach to access various 1‐acyl‐1,5‐dihydro‐2H‐pyrrol‐2‐ones in high yields. [ABSTRACT FROM AUTHOR]

A convenient procedure for the synthesis of thioesters has been developed via a palladium‐catalyzed thiocarbonylation of benzyl chlorides with sulfonyl chlorides. Various arylacetyl thioesters were produced in good yields by using sulfonyl chlorides as an odorless sulfur source. Furthermore, W(CO)6 exhibited dual roles as both a solid CO surrogate and reductant here. [ABSTRACT FROM AUTHOR]

A new procedure on palladium‐catalyzed carbonylative cyclization of N‐(2‐pyridyl)sulfonyl (N‐SO2Py)‐2‐iodoanilines with terminal alkenes has been developed for the rapid construction of dihydroquinolin‐4(1H)‐one scaffolds. Enabled by the chelating group and using benzene‐1,3,5‐triyl triformate (TFBen) as the CO source, both aromatic and aliphatic alkenes were smoothly transformed into the corresponding 2,3‐dihydroquinolin‐4(1H)‐ones in good yields with excellent regioselectivities. Notably, the reaction of aromatic alkenes produces 2‐aryl‐2,3‐dihydroquinolin‐4(1H)‐ones, while 3‐alkyl‐2,3‐dihydroquinolin‐4(1H)‐ones were obtained when aliphatic alkenes were used. This protocol has been applied in the synthesis of antitumor agent A as well. [ABSTRACT FROM AUTHOR]

We report here a general four‐component synthetic procedure for the preparation of β‐boryl ketones and β‐boryl vinyl esters. Joint catalyzed by palladium and copper catalysts, borocarbonylative reaction between vinylarenes, aryl halides/triflates, B2Pin2, and carbon monoxide proceed successfully. A variety of synthetically useful β‐boryl ketones were synthesized in good to high yields by using aryl iodides as the substrates. It is noteworthy that when aryl triflates were applied as the starting materials, β‐boryl vinyl esters were synthesized in a similar manner and with broad functional group tolerance. A rational mechanism for this reaction was also proposed. [ABSTRACT FROM AUTHOR]

• A new palladium-catalyzed carbonylative procedure for α,β-unsaturated amides synthesis. • Good to excellent yields of amides were prepared from aryl azides. • Aalkenylaluminum reagents are studied in carbonylation. • Addition of organometallic reagent to isocyanates for α,β-unsaturated amides synthesis. In this work, an interesting procedure for the synthesis of α,β-unsaturated amides from aryl azides and alkenylaluminum reagent has been developed. With palladium as the catalyst and XPhos as the ligand under carbon monoxide pressure, the desired α,β-unsaturated amides were isolated in good to excellent yields with good functional group tolerance. Remarkably, this procedure also represents an example on addition of organometallic reagent to isocyanates for α,β-unsaturated amides synthesis. [ABSTRACT FROM AUTHOR]

A novel and practical procedure for the synthesis of benzogerminones by carbonylative cyclization has been developed. With Pd(PPh3)4 as the catalyst and DABCO as the base, the desired benzogerminones were isolated in moderate to good yields with good functional group tolerance. To the best of our knowledge, this is the first procedure for benzogerminones synthesis. [ABSTRACT FROM AUTHOR]

A palladium‐catalyzed carbonylation procedure for the synthesis of benzosilinones from (2‐iodophenyl)hydrosilanes and terminal alkynes has been developed. With Pd(PPh3)4 as the catalyst and DABCO as the base, various benzosilinones were isolated in good to excellent yields with good functional group tolerance. To the best of our knowledge, this is the first example for the preparation of benzosilinones from terminal alkynes. [ABSTRACT FROM AUTHOR]

A palladium‐catalyzed four‐component carbonylative coupling reaction involving aryl halides, internal alkynes, arylboronic acids, and CO has been developed for the first time. All‐carbon substituted α‐unsaturated ketones and benzofulvenes can be selectively obtained in a highly regio‐ and stereocontrolled manner. Using Cu(TFA)2 as the additive, a series of tetrasubstituted α‐unsaturated ketones were prepared in moderate to high yields. Using more acidic Lewis acid Cu(OTf)2 as the additive, multisubstituted benzofluvenes were synthesized in moderate yields. This efficient methodology involved the formation of three new C−C bonds, and provided a divergent method for the quick construction of multisubstituted α‐unsaturated ketones and benzofulvenes from easily available starting materials. [ABSTRACT FROM AUTHOR]

An interesting strategy on palladium‐catalyzed cross‐coupling of arylboronic acids and benzonitriles has been developed. In this approach, DMSO was utilized as the methylene source and reacted with benzamides (generated in situ from benzonitriles) to form an N‐acyliminium cation, followed by palladium‐catalyzed cross‐coupling with phenylboronic acids to afford the final products. A variety of the desired products were obtained in moderate to excellent yield. An interesting strategy on palladium‐catalyzed cross‐coupling of arylboronic acid and benzonitriles has been developed. In this approach, DMSO was utilized as the methylene source and reacted with benzamides (generated in situ from benzonitriles) to form N‐acyliminium cation, followed by palladium‐catalyzed cross‐coupling with phenylboronic acids to afford the final products. A variety of the desired products were obtained in moderate to excellent yield. [ABSTRACT FROM AUTHOR]

Abstract: A palladium‐catalyzed carbonylative cascade procedure for the synthesis of benzylformamides from aryl halides has been developed. The properties of the solvent chosen play a decisive role on the selectivity of the outcomes. Non‐coordinative solvent facilitates the coordination and insertion of CO to the amino‐palladium intermediate which then provides the formamides products. While the use of coordinative solvent leads to the formation of amines. A series of functional groups, including ester, ketone, nitro and cyano, were well tolerated under our conditions. The corresponding benzylformamides products were prepared in moderate to good yields without further optimization. [ABSTRACT FROM AUTHOR]

Abstract: A palladium‐catalyzed carbonylative procedure for the synthesis of unsymmetrical ureas has been developed. This one‐pot one‐step cascade procedure is consisted by three individual processes: carbonylation, Curtius rearrangement, and nucleophilic addition. A series of unsymmetrical ureas were prepared from easily available aryl iodides and amines in moderate to excellent yields. This procedure provides a convenient and practical approach for unsymmetrical urea synthesis. [ABSTRACT FROM AUTHOR]

An interesting palladium-catalyzed procedure for the synthesis of amidines from arylsilanes, isocyanides and amines has been developed. Moderate to good yields of the desired amidines were produced in the absence of a phosphine ligand under oxidative conditions. [ABSTRACT FROM AUTHOR]

A convenient and efficient palladium-catalyzed reductive carbonylation of aryl and heteroaryl bromides has been developed. With formic acid as the CO source and sodium for-mate or formic acid as the hydrogen donor, various aromatic and heteroaromatic aldehydes were produced in good to excellent yields (53–94 %) under gas-free conditions. [ABSTRACT FROM AUTHOR]

A sustainable procedure for the synthesis of various alkyl arylacetates from benzyl alcohols has been developed. With palladium as the catalyst and organic carbonates as the green solvent and in situ activator, benzyl alcohols were carbonylated in an efficient manner without any halogen additives. [ABSTRACT FROM AUTHOR]

The sluggish kinetic rate-limiting oxygen reduction reaction (ORR) at the cathode remains the foremost issue hindering the commercialization of microbial fuel cells (MFCs). Utilization of the effect of micromolecule conjugation and the synergistic effect between Pd nanoparticles and N-rGO (nitrogen-doped reduced graphene oxide) to stabilize a precious metal onto carbon materials is a promising strategy to design and synthesize highly efficient cathode catalysts. In this study, gallic acid is used to facilitate the coupling of palladium (Pd) with N-rGO to form GN@Pd-GA via a simple hydrothermal process. Notably, the as-synthesized GN@Pd-GA as a cathode catalyst shows an approximately direct four-electron feature and demonstrates a high ORR performance in 0.1 M KOH. Furthermore, the stability and methanol tolerance of GN@Pd-GA are superior to those of the commercial Pt/C catalysts. In addition, a maximum power density of 391.06 ± 0.2 mW m−2 of MFCs equipped with GN@Pd-GA was obtained, which was 96.2% of the power density of MFCs equipped with a commercial Pt/C catalyst. [ABSTRACT FROM AUTHOR]

A convenient procedure for the synthesis of aromatic primary amides through palladium-catalyzed aminocarbonylation of aryl iodides has been developed. With ammonium hydrogen carbonate as the solid nitrogen source and formic acid as the liquid CO source, a variety of primary amides were obtained in moderate to excellent yields under gas-free conditions. [ABSTRACT FROM AUTHOR]

A versatile palladium-catalyzed double carbonylation of aryl bromides has been developed. Using Pd(OAc)2/BuPAd2 as the catalyst system and DBU as the base, under relatively low CO pressure, various α-ketoamides were produced in good yields. In order to get insight into the reaction pathway, real time NMR studies were performed as well and a correlated reaction mechanism is been given. [ABSTRACT FROM AUTHOR]

A convenient procedure for the synthesis of N-(2-carbonylaryl)benzamides has been developed. Through Pd/C-catalyzed aminocarbonylation of anthranils with various hindered and functionalized aryl iodides, the desired amides were afforded in moderate to good yields. The protocol is advantageous due to the recyclable Pd/C catalyst, safe Mo(CO)6 as the solid CO source, and environmentally benign water as solvent. No inert atmosphere protection is needed. [ABSTRACT FROM AUTHOR]

In this communication, we established an interesting palladium-catalyzed carbonylation protocol for the intramolecular cyclization of azoarenes. With Mo(CO)6 as the solid CO source and through C(sp2)−H bond activation, a series of azoarenes were transformed into the corresponding 2-arylindazolones in moderate to good yields. Notably, not only symmetrical azoarenes, but also unsymmetrical substrates underwent the reaction with excellent regioselectivity. [ABSTRACT FROM AUTHOR]

The palladium-catalyzed chemoselective carbonylation of bromoaryl triflates is reported. The selective C−Br bond versus C−OTf (OTf=triflate) bond functionalization can be remarkably tuned by the combination of the ligand [4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (Xantphos) vs. 1,1′-bis(diphenylphosphino)ferrocene (DPPF)] and the solvent (toluene vs. DMSO). The respective ligand and solvent effects are rationalized by DFT calculations. In contrast, the monodentate ligands BuPAd2 and tBu3P prefer the selective C−Br bond activation and are solvent insensitive. [ABSTRACT FROM AUTHOR]

Selective synthesis is in the core of modern organic chemistry. In this communication, a novel ligand-dependent palladium-catalyzed carbonylation procedure for the divergent synthesis of aldehydes and carboxylic acids from easily available aryl halides was established. Under the same reaction conditions, the reaction pathway could be controlled by the ligands applied to give formylated and carboxylated products selectively. Sterically hindered monodentate ligands facilitated the reductive carbonylation and provided aldehydes, whereas bidentate ligands preferred the carboxylation reaction and produced carboxylic acids. A wide range of functional groups were tolerated, and the products were, in general, obtained in moderate to excellent yields. [ABSTRACT FROM AUTHOR]

An interesting palladium-catalyzed procedure for the synthesis of perfluoroalkylated enynes from perfluoroalkyl iodides and alkynes was developed. The reaction proceeds through the addition of iodoperfluoroalkanes to terminal alkynes and subsequent Sonogashira coupling with the same alkynes. This transformation could be conducted under mild reaction conditions with high efficiency and selectivity. Good functional group compatibility was observed, and a variety of perfluoroalkylated enynes products were isolated in good to excellent yields. [ABSTRACT FROM AUTHOR]

A practical, convenient, and efficient palladium-catalyzed carbonylative Sonogashira reaction of aryl iodides was developed. With formic acid as the CO source and dicyclohexyl-carbodiimide as the activator, various alkynones were produced in good to excellent yields. [ABSTRACT FROM AUTHOR]

The achievements on palladium-catalyzed carbonylative multicomponent reactions (CMCR) have been summarized and discussed according to the type of carbonylation reaction involved. [ABSTRACT FROM AUTHOR]

An interesting procedure for the palladium-catalyzed carbonylative synthesis of 3-methyleneisoindolin-1-ones from ketimines was established. By using Mo(CO)6 (0.3 equiv.) as the solid CO source and through C(sp2)−H bond activation, the desired 3-methyleneisoindolin-1-ones were isolated in moderate to good yields. [ABSTRACT FROM AUTHOR]

A general and convenient palladium-catalyzed carbonylation procedure for the synthesis of benzofuran-2(3 H)-ones from phenols and aldehydes has been developed. With formic acid as the CO source, a variety of benzofuran-2(3 H)-ones were obtained in moderate to good yields. [ABSTRACT FROM AUTHOR]

With molybdenum hexacarbonyl as the carbon monoxide source, a general palladium-catalyzed carbonylative transformation of the C−H bond on aromatic rings to produce esters has been developed. Good yields of the corresponding products have been obtained with wide functional group tolerance and excellent regioselectivity. A variety of aliphatic alcohols are suitable reactants here. [ABSTRACT FROM AUTHOR]

Aryl formates have been extensively applied as CO sources in CO-free carbonylation reactions. However, there are no catalytic synthetic procedures for their preparation. In this manuscript, we developed a convenient palladium-catalyzed procedure for the synthesis of aryl formates. Good yields were achieved under mild reaction conditions with formic acid as the formyl source. [ABSTRACT FROM AUTHOR]

Multicomponent reactions, especially those involving four or even more reagents, have been a long-standing challenge because of the issues associated with balancing reactivity, selectivity, and compatibility. Herein, we demonstrate how the use of a reagent capsule provides straightforward access to synthetically valuable thiochromenone derivatives by a palladium-catalyzed carbonylative four-component reaction. To the best of our knowledge, this is the first example of applying a capsule to prevent catalyst poisoning and undesired side reactions of the multicomponent reaction. [ABSTRACT FROM AUTHOR]

An unexpected palladium-catalyzed carbonylative synthesis of 2,3-disubstituted chromones has been developed. Starting from 2-bromofluorobenzenes and ketones, the corresponding chromones were produced in good yields. By control experiments, this transformation was found to proceed through a sequential carbonylation/Claisen-Hasse rearrangement/intramolecular nucleophilic aromatic substitution approach (SNAr). More specifically, the reaction sequence started with a palladium-catalyzed carbonylation of the ketone with o-bromofluorobenzene to give the vinyl benzoates, which subsequently transformed into 1,3-diketones via a Claisen-Hasse rearrangement. The final products were produced after an intramolecular SNAr reaction of the in situ formed 1,3-diketone. [ABSTRACT FROM AUTHOR]

A novel palladium-catalyzed CO-gas- and autoclave-free protocol for the synthesis of 11 H-pyrido[2,1- b]quinazolin-11-ones has been developed. Quinazolinones, which are omnipresent motif in many pharmaceuticals and agrochemicals, were prepared in good yields by CH bond activation and annulation using DMF as the CO surrogate. A 13CO-labelled DMF control experiment demonstrated that CO gas was released from the carbonyl of DMF with acid as the promotor. The kinetic isotope effect (KIE) value indicated that the CH activation step may not be involved in the rate-determining step. This methodology is operationally simple and showed a broad substrate scope with good to excellent yields. [ABSTRACT FROM AUTHOR]

Aryl (pseudo)halide-based (CX) carbonylation reactions have been extensively studied during the past few decades. From both academic and synthetic points of view, the carbonylative transformation of NX bonds represents an interesting and attractive area of investigation. In light of this, the first carbonylative cross-coupling between N-chloroamines and organoboronic acids has been developed. This new type of aminocarbonylation proceeds at mild temperatures (45-55 °C) with 2 mol % Pd/C (10 wt %) as the ligand-free catalyst. Not only arylboronic acids, but also alkenyl- and alkylboronic acids can be applied as the substrates and bromide and iodide substituents in the substrates are well tolerated. Initial mechanistic investigations have also been performed. [ABSTRACT FROM AUTHOR]

A convenient procedure for the synthesis of dibenzoxazepinones has been developed. Utilizing the protocol of one-pot palladium-catalyzed aminocarbonylation/aromatic nucleophilic substitution (SNAr) sequence, with 2-aminophenols and 2-bromofluorobenzenes as the substrates, the desired dibenzo[b,e][1,4]oxazepin-11(5H)-ones were prepared in moderate to excellent yields. The broad substrate scope and functional group tolerance of the reaction makes this approach a practical method for the synthesis of valuable dibenzoxazepinone and its derivatives. Mechanistic studies suggest that aminocarbonylation proceeds prior to SNAr. [ABSTRACT FROM AUTHOR]

A concise and highly versatile method for the synthesis of functionalized isoindolinones is reported. Various 2-bromoanilines undergo palladium-catalyzed carbonylation with 2-formylbenzoic acid under a convenient and mild procedure to give good to excellent yields of the corresponding isoindolinones. Additionally, 2-halobenzaldehydes can be applied as substrates in palladium-catalyzed double-carbonylation to provide identical compounds in moderate to good yields. [ABSTRACT FROM AUTHOR]

We describe here a novel procedure for the synthesis of highly substituted 2-quinolinones. By this newly developed approach, 2-quinolinone derivatives were prepared in moderate to good yields by carbonylative cyclization of N-aryl-pyridine-2-amines and internal alkynes by CH activation. Remarkably, [Mo(CO)6] was applied as a solid CO source and the reaction proceeded in an atom economic manner. [ABSTRACT FROM AUTHOR]

A CO surrogate: In two recent studies, CO2 has not only been applied as a CO source in the hydroformylation of alkenes and the carbonylative Hiyama–Denmark coupling of aryl iodides, but more interestingly it also attenuates or improves the reactivity of the reactants. [ABSTRACT FROM AUTHOR]

A new approach for the facile synthesis of fused quinazolinone scaffolds through a palladium-catalyzed carbonylative coupling followed by an intramolecular nucleophilic aromatic substitution is described. The base serves as the key modulator: Whereas DBU gives rise to the linear isomers, Et3N promotes the preferential formation of angular products. Interestingly, a light-induced 4+4 reaction of the product was also observed. [ABSTRACT FROM AUTHOR]

Combining commercially available bromoanilines and bromobenzonitriles in a novel double carbonylation process allows for a straightforward synthesis of isoindolo[1,2-b]quinazoline-10,12-diones. At least five different CC and/or CN bonds are selectively formed in this 3-component reaction, which likely proceeds through sequential carbonylation-cyclization-isomerisation-carbonylation steps. Notably, two molecules of CO are inserted in this highly efficient palladium-catalyzed process. [ABSTRACT FROM AUTHOR]

Given the importance of quinazolinones and carbonylative transformations, a palladium-catalyzed four-component carbonylative coupling system for the synthesis of diverse 4(3 H)-quinazolinone in a concise and convergent fashion has been developed. Starting from 2-bromoanilines (1 mmol), trimethyl orthoformate (2 mmol), and amines (1.1 mmol), under 10 bar of CO, the desired products were isolated in good yields in the presence of Pd(OAc)2 (2 mol %), BuPAd2 (6 mol %) in 1,4-dioxane (2 mL) at 100 °C, using N, N-diisopropylethylamine (2 mmol) as the base. Notably, the process tolerates the presence of various reactive functional groups and is very selective for quinazolinones, and was used in the synthesis of the precursor to the bioactive dihydrorutaempine. [ABSTRACT FROM AUTHOR]

Abstract: A convenient procedure for the synthesis of N-(2-cyanoaryl)benzamides has been developed. Using aryl bromides and 2-aminobenzonitriles as the substrates, Mo(CO)6 as the CO source, the desired amides were produced in good yields. Quinazolinones were produced in good yields in a sequential manner as well. [Copyright &y& Elsevier]

We describe here a convenient and mild, carbon monoxide gas-free palladium-catalyzed procedure to obtain N-substituted phthalimides with molybdenum hexacarbonyl as carbon monoxide precursor. These conditions tolerate a number of functional groups on the benzene ring as well as a number of amines and give the corresponding phthalimides in good to excellent yields. [ABSTRACT FROM AUTHOR]

Cute CO! An interesting and straightforward procedure for the carbonylative synthesis of chromenones from readily available salicylic aldehydes and benzyl chlorides has been developed (see scheme; DPPP=1,3‐bis(diphenylphosphino)propane). In the presence of a palladium catalyst, various coumarins were produced in good to excellent yields. [ABSTRACT FROM AUTHOR]

The article discusses the organic synthesis mechanism of heterocyclic compounds through palladium catalyzed coupling reactions. It mentions that the coupling reactions utilize incorporation of carbon monoxide into the parent chemical substrate in the presence of palladium crystals. It also discusses applications of palladium catalysts in preparation of ingredients for pharmaceuticals, agrochemicals industries.

Over the last few decades, carbonylation reactions have been accepted as important chemical transformations for both academic and industrial research. Carboxylic acid derivatives are the main product of carbonylation and are widely used in organic synthesis and fine chemicals preparation. Carbonylation reactions can increase the carbon chain of parent molecules, while introducing a carbonyl group. Herein, the main developments on ruthenium- and rhodium-catalyzed carbonylation are summarized. Compared with palladium catalysts, ruthenium and rhodium catalyzed reactions are a powerful method for activating CH bonds under mild and phosphine free conditions. [ABSTRACT FROM AUTHOR]

Palladium-catalyzed carbonylative coupling reactions of aromatic halides and related compounds have undergone a rapid development during recent years. Nowadays, a plethora of palladium catalysts are available for the synthesis of ketones, alkynones, chalcones, etc., which are important intermediates in the manufacture of dyes, pharmaceuticals, agrochemicals, and other industrial products. In this critical review, we summarize the development of these carbonylative transformations with carbon nucleophiles (136 references). [ABSTRACT FROM AUTHOR]

Abstract: A novel chemoselective protocol for the carbonylative Suzuki coupling of benzyl chlorides with aryl boronic acids at low pressure of carbon monoxide has been developed. Applying a commercially available palladium acetate/PCy3 catalyst system in the presence of potassium phosphate as the base and water as the solvent the coupling reactions proceeded smoothly. To demonstrate the general applicability 12 different α-arylated acetophenones have been synthesized in moderate to good yields (41–78%) under mild conditions. [Copyright &y& Elsevier]

Abstract : A convenient one-pot process has been developed for the synthesis of benzoxazoles. Starting from aryl bromides and 1,2-dibromobenzenes palladium-catalyzed aminocarbonylation and subsequent copper-catalyzed coupling reaction gave a variety of substituted benzoxazoles in moderate to good yields. [Copyright &y& Elsevier]

Abstract: A novel procedure for the palladium-catalyzed carbonylative synthesis of acyl silanes has been developed. Starting from aryl iodides and hexamethyldisilane (HMDS) various benzoyl silanes are produced in moderate to good yields. [Copyright &y& Elsevier]