Elaborated molecular architectures including complex carbocycles, heterocycles, and polycyclic molecular structures represent an important class of organic compounds because they are ubiquitous ...structural units in a broad variety of biologically and pharmacologically relevant natural products, medicinal molecules, and functional materials. A major challenge in modern synthetic methodology is the development of strategically efficient and selective construction of these compounds from readily available starting materials. Transition‐metal‐catalyzed transformations involving Heck reaction as the pivotal step have afforded a powerful approach for accessing sophisticated polycyclic skeletons from a set of easy‐to handle starting materials, thus highlighting its potential significance in streamlining the drug discovery process. Over the past few decades, significant effort has been devoted to accessing complex polycyclic derivatives in efficient and versatile routes, and a number of powerful and direct synthetic strategies have been reported. In this review, the latest advances in transition‐metal‐catalyzed transformations involving Heck reaction as the critical step are summarized, which could be divided into six categories: 1) Heck/Sonogashira tandem reaction; 2) Heck/Suzuki tandem reaction; 3) Heck/Heck tandem reaction; 4) Heck/Hiyama tandem reaction; 5) Heck/Cacchi tandem reaction; 6) Heck/C−H bond functionalization tandem reaction.
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•Synthesis of multi-arylated pyridines from easily available β-enaminoesters and 1,3-diarylpropenes.•It undergoes oxidative coupling, intramolecular cyclization, and ...dehydro-aromatization with only loss of six hydrogens.•It has the advantages of high atom economy, easy operation, and moderate to excellent yields.
An efficient tandem reaction of β-enaminoesters and 1,3-diarylpropenes is disclosed. It undergoes oxidative coupling mediated by DDQ, subsequent intermolecular cyclization and dehydro-aromatization catalyzed by Cu/TBHP in the presence of O2. A series of multi-arylated pyridines is obtained in moderate to excellent yields.
Nickel-catalyzed carbodifunctionalization of alkenes is an efficient strategy for the construction of C–C bonds. However, applications of the strategy in dialkylation of alkenes remain underdeveloped ...due to the difficulties in suppressing competitive side reactions. We now describe a nickel-catalyzed tandem reaction by difluoroalkylation–alkylation of N-vinyl 2-pyrrolidinone with difluoroalkyl bromides and dialkylzinc reagents. The reaction can also extend to N-vinyloxazolidinone and N-vinylacetamide. This carbodifunctionalization reaction proceeds smoothly under mild reaction conditions with good functional group tolerance, providing a straightforward access to gem-difluoroalkylated 2-pyrrolidinone derivatives that are of interest in medicinal chemistry.
Shell cross-linked micelles (SCMs) containing acid sites in the shell and base sites in the core are prepared from amphiphilic poly(2-oxazoline) triblock copolymers. The materials are utilized as ...two-chamber nanoreactors for a prototypical acid–base bifunctional tandem deacetalization–nitroaldol reaction. The acid and base sites are localized in different regions of the micelle, allowing the two steps in the reaction sequence to largely proceed in separate compartments, akin to the compartmentalization that occurs in biological systems.
The front cover picture is an artistic illustration of gold associated with HFIP, represented by a golden ball surrounded with a banner. This Au/HFIP duo efficiently transformed ...alkynylnaphthaldehydes to major trans tricyclic derivatives, according to a 6‐enolendo‐exo‐trig pathway. Scope and limitations as well as mechanistic studies for this rearrangement process were described leading to tricyclic functionalized ketones. Details can be found in the Communication by Véronique Michelet and co‐workers (A. Truchon, A. Dupeux, S. Olivero, V. Michelet, Adv. Synth. Catal. 2023, 365, 2006–2012; DOI: 10.1002/adsc.202201387).
An efficient and eco-friendly protocol for synthesizing difluoromethylated oxindoles through a visible-light-induced one-pot tandem reaction of N-arylacrylamides, difluoroacetic acid and PhI(OAc)2 ...was developed. This reaction proceeded in the absence of any additive, base, metal-catalyst and external photosensitizer, using cheap CHF2CO2H as a difluoromethylation reagent and bulk biomass-derived 2-MeTHF as a solvent.
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An efficient and eco-friendly protocol for synthesizing difluoromethylated oxindoles through a visible-light induced one-pot tandem reaction of N-arylacrylamides, difluoroacetic acid and PhI(OAc)2 was developed. This reaction proceeded in the absence of any additive, base, metal-catalyst and external photosensitizer, using cheap and easily available CHF2CO2H as the difluoromethylation reagent and bulk biomass-derived 2-MeTHF as the sole solvent. 26 Examples of N-arylacrylamide substrates were investigated, and all of them successfully underwent difluoromethylation to deliver the target products in good to excellent yields.
A concise and efficient method for the synthesis of 1,4-naphthoquinones has been successfully developed involving a CuI/Cu(OTf)2/DMSO system-catalyzed intramolecular oxidative cyclization of ...(o-alkynyl)arylketones. The present protocol provided a novel approach to access functionalized 1,4-naphthoquinones from non-naphthoquinone precursors with good selectivity and functional group tolerance.
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We report a facile synthesis of monodisperse NiPd alloy nanoparticles (NPs) and their assembly on graphene (G) to catalyze the tandem dehydrogenation of ammonia borane (AB) and hydrogenation of R-NO2 ...and/or R-CN to R-NH2 in aqueous methanol solutions at room temperature. The 3.4 nm NiPd alloy NPs were prepared by coreduction of nickel(II) acetate and palladium(II) acetlyacetonate by borane-tert-butylamine in oleylamine and deposition on G via a solution phase self-assembly process. G-NiPd showed composition-dependent catalysis on the tandem reaction with G-Ni30Pd70 being the most active. A variety of R-NO2 and/or R-CN derivatives were reduced selectively into R-NH2 via G-Ni30Pd70 catalyzed tandem reaction in 5–30 min reaction time with the conversion yields reaching up to 100%. Our study demonstrates a new approach to G-NiPd-catalyzed dehydrogenation of AB and hydrogenation of R-NO2 and R-CN. The G-NiPd NP catalyst is efficient and reusable, and the reaction can be performed in an environment-friendly process with short reaction times and high yields.
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•A tandem electrode concept for CO2-to-C2+ products conversion proposed.•Spatial management of CO transport to enhance C2+ products yield.•CO utilization efficiency as the key to ...increase the C2+ products yield discussed.•A high yield of C2+ products demonstrated in Cu/ZnO tandem electrodes.
The electrochemical reduction of CO2 into C2+ products is a promising route to store renewable electricity in the form of chemical energy. The current barrier to this technique is the low efficiency of C-C coupling through dimerization of adsorbed *CO or coupling of *CO with its hydrogenated derivatives over the Cu catalyst. Tandem catalysts, which integrate Cu with another CO-generation catalyst (e.g., ZnO), can enhance the C-C coupling kinetics by increasing the local concentration of the key intermediate of CO. However, the degree of enhancement is strongly dependent on the spatial manipulation of supplementary CO transport. Herein, inspired by the reactant species concentration profile in a plug flow reactor, Cu/ZnO tandem electrodes are designed by spatially adding a ZnO catalyst layer on top of the Cu catalyst layer, in which the ZnO catalyst layer fed CO concentration progressively decreases over the Cu catalyst layer. Such a spatial management of CO transport dramatically increases the CO utilization efficiency, leading to an enhancement of Faradaic efficiency and partial current density of C2+ products by 1.2 and 3.4 times, respectively, compared to the bare Cu electrode, while by 1.3 and 1.8 times, respectively, compared to the Cu&ZnO mixed electrode.
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