Access to Perfluoroalkyl-Substituted Enones and Indolin-2-ones via Multicomponent Pd-Catalyzed Carbonylative Reactions

A comprehensive review on carbonylation reactions: catalysis by magnetic nanoparticle-supported transition metals

Magnetic catalysts have become a crucial innovation in carbonylation reactions, providing a sustainable and highly efficient means of synthesizing compounds that contain carbonyl groups. This review article explores the diverse and significant role of magnetic catalysts in various carbonylation processes, emphasizing their essential contributions to improving reaction rates, selectivity, and recyclability of catalysts. The distinctive magnetic properties of these catalysts enable straightforward separation and recovery, a feature that significantly mitigates waste and reduces environmental impact. As a result, magnetic catalysts' environmental and economic advantages position them as key players in contemporary synthetic chemistry, driving the evolution of green chemistry practices. Particularly noteworthy is the combination of magnetic nanoparticles with transition metals, resulting in the development of robust catalytic systems that exploit the complementary effects of magnetism and catalysis. Recent advances have showcased the adaptability of magnetic nanoparticles supported by transition metal catalysts in various carbonylation reactions, including carbonylative coupling, alkoxy carbonylation, thio carbonylation, and amino carbonylation. This review meticulously examines the mechanistic aspects of how magnetic fields influenced catalytic performance between 2014 and the end of 2024.

Research on transition metals for the multicomponent synthesis of benzo-fused γ-lactams

Benzo-fused γ-lactams are fundamental in medicinal chemistry, acting as essential elements for various therapeutic agents due to their structural adaptability and capability to enhance biological activity. In their synthesis, transition metals play a pivotal role as catalysts, offering more efficient alternatives to traditional methods by facilitating C-N bond formation through mechanisms like intramolecular coupling. Recent advances have especially spotlighted transition-metal-catalyzed C-H amination reactions for directly converting C(sp2)-H to C(sp2)-N bonds, streamlining the creation of these compounds. Furthermore, biocatalytic approaches have emerged, providing asymmetric synthesis of lactams with high yield and enantioselectivity. This review examined the transition metal-catalyzed synthesis techniques for producing benzo-fused γ-lactams, marking a significant leap in organic synthesis by proposing more effective, selective, and greener production methods. It serves as a valuable resource for researchers in the fields of transition metal catalysts and those engaged in synthesizing these lactams.

Ni-Catalyzed Reductive Fluoroalkylthiolation of Alkynes toward Fluoroalkylated Vinylthioethers

A Ni-catalyzed protocol for the regioselective and stereoselective three-component fluoroalkylthiolation of alkynes with fluoroalkyl halides and thiosulfonates is presented. This reductive difunctionalization provides an efficient strategy for the rapid construction of fluoroalkyl-incorporated vinylthioethers under mild conditions in moderate to good yields.

Palladium-Catalyzed Carbonylative Multicomponent Fluoroalkylation of 1,3-Enynes: Concise Construction of Diverse Cyclic Compounds

Multicomponent reactions, particularly those entailing four or more reagents, have presented a longstanding challenge due to the inherent complexities associated with balancing reactivity, selectivity, and compatibility. In this study, we describe a palladium-catalyzed multi-component fluoroalkylative carbonylation of 1,3-enynes. A series of products featuring three active functional groups-allene, fluoroalkyl, and carboxyl, were efficiently and selectively integrated in a single chemical operation. Furthermore, more intricate fluoroalkyl-substituted pyrimidinones can be constructed by simply altering the 1,3-bisnucleophilic reagent. This approach also provides a valuable strategy for the late-stage modification of naturally occurring molecules and concise construction of diverse cyclic compounds.

Palladium-catalyzed difluoroalkylative carbonylation of styrenes toward difluoropentanedioates

The introduction of fluorine atoms into organic molecules is an attractive but challenging topic. In this work, an interesting palladium-catalyzed difluoroalkylative carbonylation of aryl olefins has been developed. A wide range of aryl olefins were transformed into the corresponding difluoropentanedioate compounds with good functional-group tolerance and excellent regioselectivity. Inexpensive ethyl bromodifluoroacetate acts both as a difluoroalkyl precursor and a nucleophile here. Additionally, a scale-up reaction was also performed successfully, and further transformations of the obtained product were shown as well.

Ni-Catalyzed Reductive Fluoroalkylacylation of Alkynes for the Steroselective Synthesis of Fluoroalkylated Enones

A Ni-catalyzed three-component reductive fluoroalkylacylation of alkynes with fluoroalkyl halides and acyl chlorides is presented. This dicarbofunctionalization provides an efficient method for the synthesis of fluoroalkyl-incorporated enones under mild conditions with high yields and excellent regioselectivity and stereoselectivity.

Transition-Metal-Catalyzed Carbonylative Multifunctionalization of Alkynes

Currently, the construction of new carbon-carbon bonds and value-added structures in an atom- and step economical manner has become a continuous pursuit in the synthetic chemistry community. Since the first transition-metal-catalyzed hydroformylation of ethylene was reported by Otto Roelen in the 1930s, impressive progress has been achieved in the carbonylative functionalization of unsaturated C-C bonds. In contrast to alkenes, the carbonylative functionalization of alkynes offers tremendous potential for the construction of multisubstituted carbonyl-containing derivatives because of their two independently addressable π-systems. This review provides a timely and necessary investigation of transition-metal-catalyzed carbonylative mutifunctionalization of alkynes with the exclusion of carbonylative hydrofunctionalizations. Different transition metals including palladium, rhodium, iridium, ruthenium, iron, copper, etc. were applied to the development of novel carbonylative transformation. Various C-C, C-N, C-O, C-S, C-B, C-Si, and carbon-halogen bonds were formed efficiently and give the corresponding tri- or tetrasubstituted α,β-unsaturated ketones, diesters, and heterocycles.

Palladium-Catalyzed Perfluoroalkylative Carbonylation of Unactivated Alkenes: Access to β-Perfluoroalkyl Esters

Transition-metal-catalyzed multi-component carbonylation represents an efficient strategy for the preparation of various functionalized carbonyl-containing compounds. Herein, we report a general palladium-catalyzed perfluoroalkylative carbonylation of unactivated alkenes using inexpensive and readily available carbon monoxide as the C1 source and perfluoroalkyl halides as the coupling partner. A wide range of phenols and alcohols were transformed into the corresponding β-perfluoroalkyl esters in high yields with broad functional group tolerance and good chemoselectivity. Additionally, alkyl halides can be utilized as alkoxy source as well to give the desired esters. Moreover, several pharmaceutical and bio-active molecules were also suitable substrates for this one-pot multi-component carbonylation process to give the targeted products in good yields.

Palladium-Catalyzed Carbonylative Four-Component Synthesis of β-Perfluoroalkyl Amides

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.

Synthesis and Photochemical Application of Hydrofluoroolefin (HFO) Based Fluoroalkyl Building Block

A novel fluoroalkyl iodide was synthesized on multigram scale from refrigerant gas HFO-1234yf as cheap industrial starting material in a simple, solvent-free, and easily scalable process. We demonstrated its applicability in a metal-free photocatalytic ATRA reaction to synthesize valuable fluoroalkylated vinyl iodides and proved the straightforward transformability of the products in cross-coupling chemistry to obtain conjugated systems.

Visible light photocatalytic cross-coupling and addition reactions of arylalkynes with perfluoroalkyl iodides

Visible light photocatalytic cross-coupling and addition reactions of arylalkynes with perfluoroalkyl iodides have been developed. Through slight modifications of the reaction conditions, reactions that are selective for the preparation of the C-C coupling product (perfluoroalkyl alkynes) and the addition products (iodo-perfluoroalkyl substituted alkenes) can be achieved. These reactions work well with different types of alkynes and perfluoroalkyl iodides. As the iodide generated from the reaction can serve as a reductant to regenerate the photocatalyst from its oxidized form, no sacrificial electron donor is required.

Palladium-catalyzed multicomponent reactions: an overview

This first review on this topic focuses on the developments in the chemistry of Pd-catalyzed multi-component reactions (MCRs). MCRs are generally atom economic, ideal and eco-friendly reactions, and often the final products are generated almost without any by-products. In this review, the developments in Pd-catalyzed MCRs are categorized based on the products formed such as acyclic compounds, carbocyclic compounds, heterocyclic compounds and miscellaneous compounds. MCRs have great applications in various fields like medicinal chemistry, combinatorial synthesis, heterocyclic chemistry etc. and this review covers the literature up to 2019.

Multicomponent reactions (MCRs): a useful access to the synthesis of benzo-fused γ-lactams

Benzo-fused γ-lactam rings such as isoindolin-2-ones and 2-oxindoles are part of the structure of many pharmaceutically active molecules. They can be often synthesized by means of multicomponent approaches and recent contributions in this field are summarized in this review. Clear advantages of these methods include the efficiency in saving raw materials and working time. However, there is still a need of new catalytic systems to allow the enantioselective preparation of these heterocycles by multicomponent reactions.

Metal-catalysed radical carbonylation reactions

A review of metal-catalysed radical carbonylation reactions is presented.

Crystal structures and FT-IR spectra of three N,N-dicyclohexylmethylammonium halides C13H26N+ X − (X = Cl, Br, I)

The title compounds C13H26N+Cl− (N,N-dicyclohexylmethylammonium chloride), C13H26N+Br− (N,N- dicyclohexylmethylammonium bromide) and C13H26N+I− (N,N-dicyclohexylmethylammonium iodide) are isostructural and crystallize in the orthorhombic space group Pna21 with the lattice parameters a=7.580(1), b=19.072(1), c=9.165(1) Å, V=1324.9(1) Å3 for X=Cl, a=7.765(1), b=19.054(1), c=9.270(1) Å, V=1371.5(1) Å3 for X=Br, and a=8.102(1), b=19.084(1), c=9.535(1) Å, V=1474.2(1) Å3 for X=I with Z=4 for each compound. Their cyclohexyl groups are aligned along [010] while their halide ions are coordinated along [100] by a strong linear N–H···X (X=Cl, Br, I) hydrogen bond. Fourier-transform infrared spectra show a decreasing hydrogen bond acceptor strength from the chloride to the iodide.

Copper-Catalyzed Synthesis of Substituted Quinazolines from Benzonitriles and 2-Ethynylanilines via Carbon-Carbon Bond Cleavage Using Molecular Oxygen

A copper-catalyzed process for the synthesis of substituted quinazolines from benzonitriles and 2-ethynylanilines using molecular oxygen (O₂) as sole oxidant is described. The mild catalytic system enabled the effective cleavage of the C-C triple bond and construction of new C-N and C-C bonds in one operation. Furthermore, the compound N, N-dimethyl-4-(2-(4-(trifluoromethyl)phenyl)quinazolin-4-yl)aniline (3dj) exhibited obvious aggregation-induced emission phenomenon, and the fluorescence quantum yield (Φ_F,film) and lifetime (τ_film) were measured to be 45.5% and 5.8 ns in thin films state, respectively.