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Developing efficient near-infrared photocatalyst for organic transformations is a long but challenging goal. In a recent paper in Journal of the American Chemical Society, Shuxin Wang, Jun Xuan, Manzhou Zhu and co-workers explored the gold nanocluster-triggered near-infrared photocatalytic oxidative functionalization with high efficiency. This work cultivates a new land for the application of metal nanocluster as well as near-infrared photocatalysis. [ABSTRACT FROM AUTHOR]

A solid amino‐supported palladium catalyst is used in an oxidative domino reaction for the diastereoselective construction of alkyne‐substituted cyclopentenol compounds. This heterogeneous catalyst exhibits high efficiency and excellent chemoselectivity, as well as good recyclability. The chemoselectivity of the domino reactions was readily controlled by switching the solvent and catalyst. Asymmetric syntheses and an oxidative carbocyclization‐borylation reaction have also been developed based on the heterogeneous palladium catalyst. [ABSTRACT FROM AUTHOR]

A solid amino‐supported palladium catalyst is used in an oxidative domino reaction for the diastereoselective construction of alkyne‐substituted cyclopentenol compounds. This heterogeneous catalyst exhibits high efficiency and excellent chemoselectivity, as well as good recyclability. The chemoselectivity of the domino reactions was readily controlled by switching the solvent and catalyst. Asymmetric syntheses and an oxidative carbocyclization‐borylation reaction have also been developed based on the heterogeneous palladium catalyst. [ABSTRACT FROM AUTHOR]

A silver‐triggered heterogeneous Pd‐catalyzed oxidative carbonylation has been developed. This heterogeneous process exhibits high efficiency and good recyclability, and was utilized for the one‐pot construction of polycyclic compounds with multiple chiral centers. AgOTf was used to remove chloride ions in the heterogeneous catalyst Pd‐AmP‐CNC, thereby generating highly active PdII, which results in high efficiency of the heterogeneous catalytic system. [ABSTRACT FROM AUTHOR]

A silver‐triggered heterogeneous Pd‐catalyzed oxidative carbonylation has been developed. This heterogeneous process exhibits high efficiency and good recyclability, and was utilized for the one‐pot construction of polycyclic compounds with multiple chiral centers. AgOTf was used to remove chloride ions in the heterogeneous catalyst Pd‐AmP‐CNC, thereby generating highly active PdII, which results in high efficiency of the heterogeneous catalytic system. [ABSTRACT FROM AUTHOR]

A heterogeneous palladium‐catalyzed oxidative cyclization of enallenols has been developed for the construction of highly substituted furan and oxaborole derivatives. The heterogeneous catalyst (Pd‐AmP‐MCF) exhibits high activity, high site‐ and stereoselectivity, and efficient palladium recyclability in the transformations. [ABSTRACT FROM AUTHOR]

A heterogeneous palladium‐catalyzed oxidative cyclization of enallenols has been developed for the construction of highly substituted furan and oxaborole derivatives. The heterogeneous catalyst (Pd‐AmP‐MCF) exhibits high activity, high site‐ and stereoselectivity, and efficient palladium recyclability in the transformations. [ABSTRACT FROM AUTHOR]

A highly selective and efficient oxidative carbocyclization/borylation of enallenols catalyzed by palladium immobilized on amino‐functionalized siliceous mesocellular foam (Pd‐AmP‐MCF) was developed for diastereoselective cyclobutenol synthesis. The heterogeneous palladium catalyst can be recovered and recycled without any observed loss of activity or selectivity. The high diastereoselectivity of the reaction is proposed to originate from a directing effect of the enallenol hydroxyl group. Optically pure cyclobutenol synthesis was achieved by the heterogeneous strategy by using chiral enallenol obtained from kinetic resolution. Heterogeneous catalysis: An oxidative carbocyclization‐borylation of enallenols catalyzed by recoverable and recyclable heterogeneous Pd‐AmP‐MCF catalyst was developed for the synthesis of cyclobutenols with high diastereoselectivity (see scheme). [ABSTRACT FROM AUTHOR]

Tuning the nanoclusters' compositions and structures is critical for the performance improvement of nanoclusters. Herein, a well-known Au25( SCH2CH2Ph)18 (Au25 for short) nanocluster has been transformed to a rare cadmium doped gold nanocluster [ Au13Cd2( PPh3)6( SC2H4Ph)6( NO3)2] 2Cd( NO3)4 ( Au26Cd5 for short) by peeling and doping. Although Au25 exhibits no catalytic activity toward A3-coupling reaction under the investigated conditions, the novel cadmium doped gold nanocluster Au26Cd5 shows high catalytic activity, as well as good recyclability and substrate tolerance for the same reaction. The high catalytic activity is attributed to the cooperation between the exerted cadmium atoms and the neighbor gold atoms on the surface of Au13 icosahedron. This work has important implication for the tuning of nanoclusters' compositions and structures targeting the improvement of catalytic performance by some unusual but effective strategies. [ABSTRACT FROM AUTHOR]

A new nanocluster of atomic precision, Au44(SC2H4Ph)32, is obtained by an oxidation–decomposition–recombination (ODR) process from Au25(SC2H4Ph)18 under mild conditions with high yield (75%). Among the investigated gold nanoclusters, Au44(SC2H4Ph)32 exhibits the highest catalytic activity for the reduction of 4-nitrophenol, especially at low temperature, indicating that the catalytic properties of gold nanoclusters are not only size-dependent, but also structure-sensitive. [ABSTRACT FROM AUTHOR]

Constructing structurally robust and catalytically active metal nanoclusters for catalyzing multi‐component reactions is an interesting while challenging task. Inspired by Lewis acid and Lewis base catalysis, we realized the combination of both Lewis acid and Lewis base sites on the surface of a stable gold nanocluster Au35Cd2. The catalytic potential of Au35Cd2 in four‐component Ugi reaction was explored, demonstrating high activity and exceptional recyclability. In‐depth mechanism studies indicate that the catalytic synergy of the Lewis acid/base pair is crucial for the high efficiency of Au35Cd2‐catalyzed Ugi reaction. Bearing the stable structure, multiple activation sites and hierarchical chirality, Au35Cd2 is expected to display further interesting catalytic performance such as asymmetric catalysis. [ABSTRACT FROM AUTHOR]

An unprecedented alkylation reaction of malononitriles with enantioenriched primary allylic amines has been developed in a stereospecific manner through palladium-catalyzed sp3 C–N bond cleavage without additives at room temperature. [ABSTRACT FROM AUTHOR]

Selective functionalization of allenic C(sp2)‐H is an ideal approach to upgrading simple allenes to synthetically useful allenes, albeit suffering from challenges associated with inert reactivity and inferior selectivity. Inspired by energy chemistry, a catalytic hydrogen evolution reaction (HER) strategy was leveraged to selectively activate weakly acidic allene C(sp2)‐H bonds in a reductive mode. An array of [Co2O2] metallacycle complexes were readily devised starting from amino acids, and they were demonstrated as robust HER catalysts, which would selectively break allenic C(sp2)‐H bonds to release hydrogen. With the newly developed HER catalyst, regioselective electrochemical functionalization of allenic C(sp2)‐H with alcoholic α C(sp3)‐H was unprecedentedly achieved. This strategy features excellent regioselectivity, unconventional chemoselectivity, good functional‐group tolerance (62 examples), and mild conditions. Mechanism experiments revealed a reactive hydroxy‐coordinated cobalt(II) species in the reaction. Density functional theory (DFT) calculations were also conducted to rationalize the regioselectivity observed in the reaction. [ABSTRACT FROM AUTHOR]

Selective functionalization of allenic C(sp2)‐H is an ideal approach to upgrading simple allenes to synthetically useful allenes, albeit suffering from challenges associated with inert reactivity and inferior selectivity. Inspired by energy chemistry, a catalytic hydrogen evolution reaction (HER) strategy was leveraged to selectively activate weakly acidic allene C(sp2)‐H bonds in a reductive mode. An array of [Co2O2] metallacycle complexes were readily devised starting from amino acids, and they were demonstrated as robust HER catalysts, which would selectively break allenic C(sp2)‐H bonds to release hydrogen. With the newly developed HER catalyst, regioselective electrochemical functionalization of allenic C(sp2)‐H with alcoholic α C(sp3)‐H was unprecedentedly achieved. This strategy features excellent regioselectivity, unconventional chemoselectivity, good functional‐group tolerance (62 examples), and mild conditions. Mechanism experiments revealed a reactive hydroxy‐coordinated cobalt(II) species in the reaction. Density functional theory (DFT) calculations were also conducted to rationalize the regioselectivity observed in the reaction. [ABSTRACT FROM AUTHOR]

Carbon monoxide, which is an abundant and inexpensive carbonyl source, has been widely applied to synthesize carbonyl-containing compounds, for example ketones, esters, and amides. These types of compounds are ubiquitous in natural products, pharmaceuticals, as well as in functional materials. This review focuses on the palladium-catalyzed dehydrogenative C–H/X–H (X = C, N, O) carbonylation transformations under oxidative conditions. The related C–H bonds here include C(sp)–H, C(sp2)–H, and C(sp3)–H bonds. From a step- and atom-economy perspective, transition metal-catalyzed oxidative dehydrogenative C–H/X–H carbonylation reactions with CO constitute one of the most efficient strategies for the construction of versatile carbonyl groups, without the requirement of pre-functionalized substrates. [ABSTRACT FROM AUTHOR]

The cover picture shows the structure transformation from a well-known gold nanocluster Au25(SCH2CH2Ph)18 (Au25 for short) to a novel cadmium doped gold nanocluster [Au13Cd2(PPh3)6(SC2H4Ph)6(NO3)2]2Cd(NO3)4 (Au26Cd5 for short) by a combined peeling and doping process. Although the mother nanocluster Au25 is inactive, the as-prepared Au26Cd5 exhibits high catalytic activity, as well as good recyclability and substrate tolerance at room temperature. The high catalytic activity is attributed to the cooperation between the exerted cadmium atoms and the neighbor gold atoms in the Au13 icosahedron based on some experimental results. More details are discussed in the article by Wu et al. on page 567-571. [ABSTRACT FROM AUTHOR]

The reaction proceeds with perfect retention of optical purity and alkene geometry. [ABSTRACT FROM AUTHOR]

A gold nanocluster Au17Cd2(PNP)2(SR)12 (PNP=2,6‐bis(diphenylphosphinomethyl)pyridine, SR=4‐MeOPhS) consisting of an icosahedral Au13 kernel, two Au2CdS6 staple motifs, and two PNP pincer ligands has been designed, synthesized and well characterized. This cadmium and PNP pincer ligand co‐modified gold nanocluster showed high catalytic efficiency in the KA2 reaction, featuring high TON, mild reaction conditions, broad substrate scope as well as catalyst recyclability. Comparison of the catalytic performance between Au17Cd2(PNP)2(SR)12 and the structurally similar single cadmium (or PNP) modified gold nanoclusters demonstrates that the co‐existence of the cadmium and PNP on the surface is crucial for the high catalytic activity of the gold nanocluster. This work would be enlightening for developing efficient catalysts for cascade reactions and discovering the catalytic potential of metal nanoclusters in organic transformations. [ABSTRACT FROM AUTHOR]

A gold nanocluster Au17Cd2(PNP)2(SR)12 (PNP=2,6‐bis(diphenylphosphinomethyl)pyridine, SR=4‐MeOPhS) consisting of an icosahedral Au13 kernel, two Au2CdS6 staple motifs, and two PNP pincer ligands has been designed, synthesized and well characterized. This cadmium and PNP pincer ligand co‐modified gold nanocluster showed high catalytic efficiency in the KA2 reaction, featuring high TON, mild reaction conditions, broad substrate scope as well as catalyst recyclability. Comparison of the catalytic performance between Au17Cd2(PNP)2(SR)12 and the structurally similar single cadmium (or PNP) modified gold nanoclusters demonstrates that the co‐existence of the cadmium and PNP on the surface is crucial for the high catalytic activity of the gold nanocluster. This work would be enlightening for developing efficient catalysts for cascade reactions and discovering the catalytic potential of metal nanoclusters in organic transformations. [ABSTRACT FROM AUTHOR]

The method is based on the exploiting of the free amino group as an effective leaving group. [ABSTRACT FROM AUTHOR]

Alloynanoparticles with atomic monodispersity is ofimportancefor some fundamental research (e.g., the investigation of active sites).However, the controlled preparation of alloy nanoparticles with atomicmonodispersity has long been a major challenge. Herein, for the firsttime a unique method, antigalvanic reduction (AGR), is introducedto synthesize atomically monodisperse Au25Ag2(SC2H4Ph)18in high yield (89%)within 2 min. Interestingly, the two silver atoms in Au25Ag2(SC2H4Ph)18do notreplace the gold atoms in the precursor particle Au25(SC2H4Ph)18but collocate on Au25, which was supported by experimental and calculated results. Also,the two silver atoms are active to play roles in stabilizing the alloynanoparticle, triggering the nanoparticle fluorescence and catalyzingthe hydrolysis of 1,3-diphenylprop-2-ynyl acetate. [ABSTRACT FROM AUTHOR]

Thiolates endow metal nanoclusters with stability while sometimes inhibit the catalytic activity due to the strong M−S interaction (M: metal atom). To improve the catalytic activity and keep the stability to some extent, one strategy is the partial phosphorization of thiolated metal nanoclusters. This is demonstrated by successful partial phosphorization of Au23(SC6H11)16 and by revealing that the products Au22(SC6H11)14(PPh3)2 and Au22(SC6H11)12(PPh3)4, with varied degree of phosphorization, both show excellent activity in the photocatalytic oxidation of thioanisole without notable reduction of stability. Furthermore, Au22(SC6H11)12(PPh3)4 exhibits better photoluminescence performance than the mother nanocluster Au23(SC6H11)16, indicating that partial phosphorization can also improve some other performance(s) except for the catalytic performance. The intermediates Au22‐xCux(SC6H11)12(PPh3)4 (x=1, 2) in the transformation from Au23(SC6H11)16 (Au22(SC6H11)14(PPh3)2) to Au22(SC6H11)12(PPh3)4 were captured and identified by mass spectrometry and single crystal X‐ray diffraction, which throws light on the understanding of the non‐alloyed anti‐galvanic reaction. [ABSTRACT FROM AUTHOR]

[Display omitted] • An efficient strategy to incorporate Cu2+ into nanoclusters was developed. • The incorporation induced enhancement in nanocluster catalysis was revealed. • The atomically precise composition/structure of the nano-catalyst was determined. • The Au 13 Cu 2 catalyst outperforms the classic bicatalyst for Sonogashira reaction. • Mechanism of Au 13 Cu 2 catalyzed-Sonogashira reaction was proposed. Pd together with CuI has been well known as the catalyst towards Sonogashira reaction, which provides an effective route to functional alkynes. However, the achievement of high activity and selectivity of this catalytic system is still challenging in some cases. Illustrative examples include their low activity for aryl chloride substrates, and switched selectivity to oxidative coupling products in air atmosphere. In this work, a Cu-incorporated Au 13 nanocluster [Au 13 Cu 2 (PPh 3) 6 (SC 2 H 4 Ph) 6 ]+[NO 3 ]- (Au 13 Cu 2) was designed and prepared in high yield via rapid synthesis. This atomically precise nanocluster shows the potential to be a novel catalytic system for Sonogashira reaction, featuring high activity and selectivity, as well as good recyclability even in air atmosphere. [ABSTRACT FROM AUTHOR]

An efficient cross-coupling reaction of N-allylic sulfonimides with organozinc reagents has been developed. In the presence of 1 mol-% of Pd2(dba)3, a range of N-allylic sulfonimides smoothly couple with various organozinc reagents at room temperature to give the corresponding ( E)-alkene products in moderate to excellent yields and with good to exclusive α-selectivity. It is noteworthy that allyl ether, benzyl ether, and ester are tolerated under the reaction conditions. [ABSTRACT FROM AUTHOR]

Revealing structural isomerism in nanoparticles using single-crystal X-ray crystallography remains a largely unresolved task, although it has been theoretically predicted with some experimental clues. Here we report a pair of structural isomers, Au38T and Au38Q, as evidenced using electrospray ionization mass spectrometry, X-ray photoelectron spectroscopy, thermogravimetric analysis and indisputable single-crystal X-ray crystallography. The two isomers show different optical and catalytic properties, and differences in stability. In addition, the less stable Au38T can be irreversibly transformed to the more stable Au38Q at 50 °C in toluene. This work may represent an important advance in revealing structural isomerism at the nanoscale. [ABSTRACT FROM AUTHOR]

The process is applied to a broad spectrum of substrates where high regioselectivity is observed. [ABSTRACT FROM AUTHOR]