Carbonyl Olefination Research Articles

Cyclization Strategies in Carbonyl–Olefin Metathesis: An Up-to-Date Review

The metathesis reaction between carbonyl compounds and olefins has emerged as a potent strategy for facilitating swift functional group interconversion and the construction of intricate organic structures through the creation of novel carbon–carbon double bonds. To date, significant progress has been made in carbonyl–olefin metathesis reactions, where oxetane, pyrazolidine, 1,3-diol, and metal alkylidene have been proved to be key intermediates. Recently, several reviews have been disclosed, focusing on distinct catalytic approaches for achieving carbonyl–olefin metathesis. However, the summarization of cyclization strategies for constructing aromatic heterocyclic frameworks through carbonyl–olefin metathesis reactions has rarely been reported. Consequently, we present an up-to-date review of the cyclization strategies in carbonyl–olefin metathesis, categorizing them into three main groups: the formation of monocyclic compounds, bicyclic compounds, and polycyclic compounds. This review delves into the underlying mechanism, scope, and applications, offering a comprehensive perspective on the current strength and the limitation of this field.

Formation and reactivity of electrogenerated lewis acids by oxidation of Bu4NB(C6F5)4 under weakly coordinating conditions

This study explores the generation and application of electrogenerated Lewis acids (EGLA) through anodic oxidation of tetrakis(pentafluorophenyl)borate, B(C6F5)4−, in weakly coordinating electrolytes. Employing Bu4NB(C6F5)4/CH2Cl2 as the electrolyte, bis(perfluorophenyl)borane (PFB), a highly reactive Lewis acid, was generated and utilized in various organic transformations. Cyclic voltammetry confirmed the onset of oxidation at 1.8 V vs. Ag/AgNO3, which led to the formation of the EGLA species. The EGLA system was successfully applied for the defluorination of 1-fluoroadamantane and other alkyl fluorides in both batch and flow electrolysis systems. Additionally, EGLA was effective in catalyzing diverse reactions, including Friedel-Crafts dimerization, deoxygenation of triphenylmethanol, and carbonyl–olefin metathesis, outperforming traditional Lewis acids, such as PFB and tris(pentafluorophenyl)borane. The reactivity of EGLA is strongly dependent on the solvent environment, with weakly coordinating solvents being critical for maintaining activity. This study highlights the potential of EGLA as a versatile and highly active catalyst for a broad range of organic transformations, emphasizing the importance of solvent selection in maximizing its reactivity.

Polyoxometalates Based Catalysts for Carbonylation Reactions: A Review.

As a type of diverse and structurally adjustable metal-oxo clusters, polyoxometalates (POMs) based materials have been extensively applied as a catalysis in various valuable reactions. This review summarized recent progress in the application of POMs-based catalysts for various carbonylation reactions including (1). Carbonylation of olefins, (2). Carbonylation of formaldehyde, (3). Carbonylation of methanol or dimethyl ether, (4). Oxidative carbonylation of methane, (5). Oxidative carbonylation of phenol and (6). Reductive carbonylation of nitrobenzene. A brief perspective on POMs-based catalysts for the carbonylation reactions is proposed.

الدراسة التركيبية والطاقية لأيونات الليثيوم مع الأحماض الدهنية ميثيل استر [[FAME (9Z-18:1) + Li+ باستخدام الطريقة الكيميائية الكمومية (PM3)

Lithium (Li) ions are being used in a variety of fields ranging from energy storage to the treatment of mental illnesses including bipolar disorder and schizophrenia. Lithium caton (Li+) is able to form cationic adducts with various compounds and they can stabilize the biomacromolecules that interact with. Here, the interaction of lithium ions with fatty acid methyl ester [FAME (9Z-18:1)] has been theoretically investigated to gain insight into the structure and energetics of [FAME (9Z-18:1) + Li+]. All theoretical calculations were performed using Gaussian09 software via a graphic user interface. Geometry optimisations with harmonic vibrational analysis of conformations for chelated and extended forms of [FAME (9Z-18:1) + Li+] were carried out using semi-empirical method PM3. To obtain accurate energetic, zero-point energy (ZPE) corrections were included in all optimized energies and relative energies between conformers. The calculations indicated that the chelated form is relatively more stable than extended forms by 25 and 118 kJmol-1 when lithium is bound to the carbonyl oxygen (O-Li+) or olefin (C=C-Li+), respectively. The comparison between the relative stabilization energies of extended (O-Li+) versus extended (C=C-Li+) reveals that the lithium cation energetically prefers to bind to with carbonyl oxygen over the carbon-carbon double bond. Keywords: lithium ions, geometry optimization, sim-empirical method, Gaussian 09.

Computational Exploration of 1,2-Carboamine Carbonylation Catalyzed by Nickel.

Nickel-catalyzed carbonylation of alkenes is a stereoselective and regioselective method for the synthesis of amide compounds. Theoretical predictions with density functional theory calculations revealed the mechanism and origin of stereoselectivity and regioselectivity for the nickel-catalyzed carbonylation of norbornene. The carbonylation reaction proceeds through oxidative addition, migration insertion of alkenes, and subsequent reduction elimination to afford cis-carbonylation product. The C-N bond activation of amides is unfavorable because the oxidative addition ability of the C-C bond is stronger than that of the C-N bond. The determining step of stereoselectivity is the migratory insertion of the strained olefin. The structural analysis shows that steroselectivity is controlled by the steric hindrance of methyl groups to olefins and substituents to IMes in ligands.

Identification of a potent palladium-aryldiphosphine catalytic system for high-performance carbonylation of alkenes

The development of stable and efficient ligands is of vital significance to enhance the catalytic performance of carbonylation reactions of alkenes. Herein, an aryldiphosphine ligand (L11) bearing the [Ph2P(ortho-C6H4)]2CH2 skeleton is reported for palladium-catalyzed regioselective carbonylation of alkenes. Compared with the industrially successful Pd/1,2-bis(di-tert-butylphosphinomethyl)benzene catalyst, catalytic efficiency catalyzed by Pd/L11 on methoxycarbonylation of ethylene is obtained, exhibiting better catalytic performance (TON: >2,390,000; TOF: 100,000 h−1; selectivity: >99%) and stronger oxygen-resistance stability. Moreover, a substrate compatibility (122 examples) including chiral and bioactive alkenes or alcohols is achieved with up to 99% yield and 99% regioselectivity. Experimental and computational investigations show that the appropriate bite angle of aryldiphosphine ligand and the favorable interaction of 1,4-dioxane with Pd/L11 synergistically contribute to high activity and selectivity while the electron deficient phosphines originated from electron delocalization endow L11 with excellent oxygen-resistance stability.

Direct Synthesis of γ-Amino Acid Derivatives via Cobalt-Catalyzed Aminoalkylative Carbonylation of Alkenes

Direct Synthesis of γ-Amino Acid Derivatives via Cobalt-Catalyzed Aminoalkylative Carbonylation of Alkenes

Development of ligand-free Pd@TiO2 catalyst for efficient perfluoroalkylative carbonylation of terminal alkenes

The development of heterogeneous catalysts for the difunctionalization of olefins is of great scientific significance because of their sustainability in the manufacturing industry. Herein, we report a ligand free Pd@TiO2 catalyst that realized the perfluoroalkyl carbonylation of terminal olefins using carbon monoxide as the C1 source, providing sustainable access to β-perfluoroalkyl esters. This catalyst shows high activity, good recyclability, and broad functional group tolerance. The catalytic system developed here can reduce noble metal use and avoid using precious homogeneous phosphorus ligands, which are also toxic to the environment.

Olefination of aldehydes with alpha-halo redox-active esters

A simple and practical decarboxylative carbonyl olefination is described. This procedure explores the application of α-halo NHPI redox-active esters in organic chemistry.

Carbonyl Olefin Metathesis and Dehydrogenative Cyclization of Aromatic Ketones and gem‐Difluoroalkenes

AbstractThe beauty of one‐pot cascade reaction lies in the efficient disconnection and construction of several bonds in a single reaction flask, without the isolation of any intermediates. Herein, we report the first photoinduced thermally promoted cascade reactions of readily available aromatic ketones and aromatic gem‐difluoroalkenes for the synthesis of phenanthrenes which possess potential utility in drug design and materials science. The reaction combines carbonyl‐olefin metathesis (cascade photoinduced [2+2] cyclization and thermally controlled retro [2+2] cyclization) and dehydrogenative cyclization (cascade photoinduced conrotatory 6π electrocyclization and collidine‐promoted dehydrogenative aromatization) together in one pot. The oxidant‐free, acid‐free and metal‐free reaction shows broad substrate scope and wide functional group tolerance.

Carbonyl Olefin Metathesis and Dehydrogenative Cyclization of Aromatic Ketones and gem-Difluoroalkenes.

The beauty of one-pot cascade reaction lies in the efficient disconnection and construction of several bonds in a single reaction flask, without the isolation of any intermediates. Herein, we report the first photoinduced thermally promoted cascade reactions of readily available aromatic ketones and aromatic gem-difluoroalkenes for the synthesis of phenanthrenes which possess potential utility in drug design and materials science. The reaction combines carbonyl-olefin metathesis (cascade photoinduced [2+2] cyclization and thermally controlled retro [2+2] cyclization) and dehydrogenative cyclization (cascade photoinduced conrotatory 6π electrocyclization and collidine-promoted dehydrogenative aromatization) together in one pot. The oxidant-free, acid-free and metal-free reaction shows broad substrate scope and wide functional group tolerance.

Regiodivergent Carbonylation of Alkenes: Selective Palladium-Catalyzed Synthesis of Linear and Branched Selenoesters.

An unprecedented regiodivergent palladium-catalyzed carbonylation of aromatic alkenes has been developed. Utilizing commercially available Pd(CH3 CN)2 Cl2 in the presence of 1,1'-ferrocenediyl-bis(tert-butyl(pyridin-2-yl)phosphine) ligand L8 diverse selenoesters are obtained in a straightforward manner. Key to success for the control of the regioselectivity of the carbonylation step is the concentration of the acidic co-catalyst. This general protocol features wide functional group compatibility and good regioselectivity. Mechanistic studies suggest that the presence of stoichiometric amounts of acid changes the properties and coordination mode of the ligand leading to reversed regioselectivity.

Regiodivergent Carbonylation of Alkenes: Selective Palladium‐Catalyzed Synthesis of Linear and Branched Selenoesters

AbstractAn unprecedented regiodivergent palladium‐catalyzed carbonylation of aromatic alkenes has been developed. Utilizing commercially available Pd(CH3CN)2Cl2 in the presence of 1,1′‐ferrocenediyl‐bis(tert‐butyl(pyridin‐2‐yl)phosphine) ligand L8 diverse selenoesters are obtained in a straightforward manner. Key to success for the control of the regioselectivity of the carbonylation step is the concentration of the acidic co‐catalyst. This general protocol features wide functional group compatibility and good regioselectivity. Mechanistic studies suggest that the presence of stoichiometric amounts of acid changes the properties and coordination mode of the ligand leading to reversed regioselectivity.

Cobalt-catalyzed aminoalkylative carbonylation of alkenes toward direct synthesis of γ-amino acid derivatives and peptides

γ-Amino acids and peptides analogues are common constituents of building blocks for numerous biologically active molecules, pharmaceuticals, and natural products. In particular, γ-amino acids are providing with better metabolic stability than α-amino acids. Herein we report a multicomponent carbonylation technology that combines readily available amides, alkenes, and the feedstock gas carbon monoxide to build architecturally complex and functionally diverse γ-amino acid derivatives in a single step by the implementation of radical relay catalysis. This transformation can also be used as a late-stage functionalization strategy to deliver complex, advanced γ-amino acid products for pharmaceutical and other areas.

Transition-Metal-Free and Selective Deconstructive Carbonyl Olefination of α-Hydroxy Ketones: A Complementary Approach to Knoevenagel Reaction

AbstractWhile the carbonyl olefination has been extensively studied and well documented, use of α-hydroxy ketones as precursors for the carbonyl olefination is not reported, till date. Herein, a transition-metal-free and selective Knoevenagel-type deconstructive carbonyl olefination of α-hydroxy ketones using arylacetonitriles under mild reaction conditions is presented. The reaction affords valuable scaffolds of acrylonitriles with the use of α-hydroxy ketones as precursors for carbonyl olefination.

Cobalt-Catalyzed Multicomponent Carbonylation of Olefins: Efficient Synthesis of β-Perfluoroalkyl Imides, Amides, and Esters

A general and broadly applicable cobalt-catalyzed multicomponent 1,2-perfluoroalkylation carbonylation of alkenes has been developed. This protocol allows the synthesis of β-perfluoroalkyl-substituted amides, esters, and related derivatives using olefins, carbon monoxide, commercially accessible perfluoroalkyl iodides, and a variety of nucleophiles including low nucleophilic amides and urea derivatives in a one-pot manner. As an example, readily available trifluoroiodomethane can be utilized forming pharmaceutically relevant β-trifluoromethylated amides. To showcase the application potential, the perfluoroalkylation carbonylation process was applied to selected current drugs and biologically active molecules. The methodology permits a straightforward increase of the molecular complexity of olefins toward functionalized perfluoroalkylated building blocks in a regioselective manner.

Wittig and Wittig–Horner Reactions under Sonication Conditions

Carbonyl olefinations are among the most important organic syntheses that form C=C bonds, as they usually have high yields and in addition offer excellent stereoselectivity. Due to these advantages, carbonyl olefinations have important pharmaceutical and industrial applications. These reactions contain an additional step of an α-functionalized carbanion to an aldehyde or ketone to produce alkenes, but syntheses performed using metal carbene complexes are also known. The Wittig reaction is an example of carbonyl olefination, one of the best ways to synthesize alkenes. This involves the chemical reaction between an aldehyde or ketone with a so-called Wittig reagent, for instance phosphonium ylide. Triphenylphosphine-derived ylides and trialkylphosphine-derived ylides are the most common phosphorous compounds used as Wittig reagents. The Wittig reaction is commonly involved in the synthesis of novel anti-cancer and anti-viral compounds. In recent decades, the use of ultrasound on the Wittig reaction (and on different modified Wittig syntheses, such as the Wittig-Horner reaction or the aza-Wittig method) has been studied as a green synthesis. In addition to the advantage of green synthesis, the use of ultrasounds in general also improved the yield and reduced the reaction time. All of these chemical syntheses conducted under ultrasound will be described further in the present review.

Polyhaloalkanes as the C1 source: radical-mediated migratory carbonylation of alkenes with polyhaloalkanes toward α,β-unsaturated carbonyls

An unprecedented copper-promoted radical-mediated alkenyl C(sp2)–H carbonylation of alkenes with polyhaloalkanes for divergently producing α,β-unsaturated esters and aldehydes is presented.

Highly regioselective C–H carbonylation of alkenes with phenyl formateviaaryl to vinyl 1,4-palladium migration

A novel approach to synthesize β,β-diaryl substituted α,β-unsaturated esters in high efficiency and with excellent regio- and stereoselectivities was developed.

A cis-β-iron(III) SALPN catalyst for hydrogen atom transfer reductions and olefin cross couplings.

An inexpensive Fe(III) SALPN catalyst for MHAT reactions such as reductions of α,β-unsaturated carbonyl compounds and olefin cross couplings is reported. The majority of these reactions proceeded in good yields and high stereoselectivities with low catalyst loadings at room temperature.