Decarboxylative Cross-coupling Reactions Research Articles

Visible-Light-Mediated Decarboxylative Thiocyanation of Cinnamic acids: An Efficient Photocatalytic Approach to the Synthesis of (E)-Vinyl Thiocyanates

A simple and novel methodology for the synthesis of vinyl thiocyanates from decarboxylative cross-coupling reaction of cinnamic acids with KSCN under the synergistic interactions of visible light irradiation, Cs2CO3, Rose Bengal as the photocatalyst and air as the terminal oxidant at room temperature is reported. The reaction takes place by a radical pathway as evidenced from our experiments and literature. The report is the first example on the visible-light mediated thiocyanation of cinnamic acids, which employs environmentally benign and inexpensive starting materials and is characterized by easily removable by-product CO2.

Decarboxylative Cross-Coupling of Acyl Fluorides with Potassium Perfluorobenzoates

We report the transition metal-free decarboxylative cross-coupling reactions of acyl fluorides with potassium perfluorobenzoates. Compared with traditional transition metal-catalyzed cross-couplings, this protocol presents an extremely environmentally benign pathway to afford unsymmetrical diaryl ketones. To install perfluorophenyl groups, this method highlights highly selective, inexpensive, and nontoxic conditions. The reaction system tolerates various functional groups in acyl fluorides. Remarkably, all of the starting materials can be prepared from abundant carboxylic acids and the reaction proceeds without any catalysts and additives.

Approaching the Integer-Charge Transfer Regime in Molecularly Doped Oligothiophenes by Efficient Decarboxylative Cross-Coupling.

A library of symmetrical linear oligothiophene was prepared employing decarboxylative cross-coupling reaction as the key transformation. Thiophene potassium carboxylate salts were used as cross-coupling partners without the need of co-catalyst, base, or additives. This method demonstrates complete chemoselectivity and is a comprehensive greener approach compared to the existing methods. The modularity of this approach is demonstrated with the preparation of discreet oligothiophenes with up to 10 thiophene repeat units. Symmetrical oligothiophenes are prototypical organic semiconductors where their molecular electrical doping as a function of the chain length can be assessed spectroscopically. An oligothiophene critical length for integer charge transfer was observed to be 10 thiophene units, highlighting the potential use of discrete oligothiophenes as doped conduction or injection layers in organic electronics applications.

Application of Palladium-Catalyzed Cross-Coupling Reactions in Organic Synthesis.

Palladium-catalyzed cross-coupling reactions have gained a continuously growing interest of synthetic organic chemists. The present review gives a brief account of applications of the palladium-catalyzed cross-coupling reactions in comprehensive synthesis, viz., the Heck, Stille, Suzuki-Miyaura, Negishi, Sonogashira, Buchwald-Hartwig, Ullmann and the Oxidative, decarboxylative cross-coupling reactions, with particular emphasis on the synthesis of heterocyclic compounds.

AgNO3-catalyzed decarboxylative cross-coupling reaction: an approach to coenzyme Q

High yields. Gram-scale synthesis. Csp2–H functionalization. Decarboxylative cross-coupling.

Metal-Catalyzed Ionic Decarboxylative Cross-Coupling Reactions of C(sp3) Acids: Reaction Development, Mechanisms, and Application

The direct transition-metal-catalyzed conversion of carboxylic acid groups into other C–C or C–X bonds provides a complementary bond disconnection to traditional cross-coupling manifolds. Decarboxy...

Stereoselective C(sp2)-H Alkylation of Enamides with Unactivated Aliphatic Carboxylic Acids via Decarboxylative Cross-Coupling Reactions.

An efficient and straightforward stereoselective alkylation reaction of enamides using commercially available and easily accessible unactivated alkyl carboxylic acids as alkylating agents is described, giving rise to a diverse array of synthetically important and geometrically defined β-alkylated enamides bearing primary, secondary, or tertiary alkyl moieties. This transformation also shows excellent functional group tolerance, satisfying atom economy, and operational simplicity.

Catalytic enantioselective addition of organometallics to unprotected carboxylic acids

Conjugate addition of organometallics to carbonyl based Michael acceptors is a widely used method that allows the building of new carbon-carbon (C-C) bonds and the introduction of chirality in a single step. However, conjugate additions to the simplest Michael acceptors, namely unprotected, unsaturated carboxylic acids, are considered to be prohibited by the fact that acid-base reactions overpower any other type of reactivity, including nucleophilic addition. Here we describe a transient protecting group strategy that allows efficient catalytic asymmetric additions of organomagnesium reagents to unprotected α,β-unsaturated carboxylic acids. This unorthodox pathway is achieved by preventing the formation of unreactive carboxylate salts by means of a reactive intermediate, allowing modifications of the carbon chain to proceed unhindered, while the stereochemistry is controlled with a chiral copper catalyst. A wide variety of β-chiral carboxylic acids, obtained with excellent enantioselectivities and yields, can be further transformed into valuable molecules through for instance catalytic decarboxylative cross-coupling reactions.

Basic Cu/ETS-10-N Catalyst Induced the Chemisorption and Alkyl Radical Formation of the Substrates Enhanced the Cinnamic Acid Decarboxylative Cross-Coupling Reaction Activity

Development of a high-efficiency heterogeneous catalyst for modern organic synthesis is greatly important. Herein, a nanosized ETS-10 zeolite (ETS-10-N) with strong Lewis basicity was synthesized, and used as support for prepared Cu catalyst (Cu/ETS-10-N) showing superior catalytic activity and selectivity in the decarboxylative cross-coupling of cinnamic acid and tetrahydrofuran, as compared to acidic mesoporous Beta and conventional bulk ETS-10 zeolite supported Cu catalysts. The strong Lewis basic site in the Cu/ETS-10-N not only could facilitate the formation of the alkyl radical transformed from tetrahydrofuran, but also could favor the chemisorption of cinnamic acid and activate the carbon–carbon double bond, enhancing the catalyst activity. Additionally, the Cu2+ and Cu+ species in the Cu/ETS-10-N could coordinated with the carboxylate oxygen atoms derived from cinnamic acid, improving the reaction activity of the substrate.

Synthesis of peri-Diarylated Naphthalimides via Double Decarboxylative Cross-Coupling Reaction

A facile method for the synthesis of peri-diarylated naphthalimides was developed by using a palladium-catalyzed double decarboxylative cross-coupling reaction. The present work offers a convenient approach for tuning the optical properties of naphthalimide derivatives.

3-Amino-fluorene-2,4-dicarbonitriles (AFDCs) as Photocatalysts for the Decarboxylative Arylation of α-Amino Acids and α-Oxy Acids with Arylnitriles.

1-(4-(9 H-Carbazol-9-yl)phenyl)-3-amino-9 H-fluorene-2,4-dicarbonitrile as a new photocatalyst for the decarboxylative cross-coupling reaction of α-amino acids or α-oxy carboxylic acids with arylnitriles is described. This light-driven reaction enables a variety of benzylic amines and ethers to be prepared from readily available starting materials under mild conditions.

One-Pot Electrochemical Nickel-Catalyzed Decarboxylative Sp2-Sp3 Cross-Coupling.

A one-pot electrochemical nickel-catalyzed decarboxylative sp2-sp3 cross-coupling reaction has been developed using redox-active esters prepared in situ from alkyl carboxylates and N-hydroxyphthalimide tetramethyluronium hexafluorophosphate (PITU). This undivided cell one-pot method enables C-C bond formation using inexpensive, benchtop-stable reagents with isolated yields up to 95% withgood functional group tolerance, which includes nitrile, ketone, ester, alkeneand selectivity over other aromatic halogens.

Recent developments in decarboxylative cross-coupling reactions between carboxylic acids and N-H compounds.

Carboxylic acids and their derivatives are ubiquitous compounds in organic chemistry, and are widely commercially available in a large structural variety. Recently, carboxylic acids have been frequently used as non-toxic and environmentally benign alternatives to traditional organohalide coupling partners in various carbon–carbon and carbon–heteroatom cross-coupling reactions. Along this line, several methods have been reported for the synthesis of nitrogen-containing organic compounds through decarboxylative cross-coupling reactions between carboxylic acids and N–H compounds. This review focuses on recent advances and discoveries on these reactions with special attention on the mechanistic aspects of the reactions.

Photoredox-catalyzed stereoselective alkylation of enamides with N-hydroxyphthalimide esters via decarboxylative cross-coupling reactions.

Stereoselective β-C(sp2)-H alkylation of enamides with redox-active N-hydroxyphthalimide esters via a photoredox-catalyzed decarboxylative cross-coupling reaction is demonstrated. This methodology features operational simplicity, broad substrate scopes, and excellent stereoselectivities and functional group tolerance, affording a diverse array of geometrically defined and synthetically valuable enamides bearing primary, secondary or tertiary alkyl groups in satisfactory yields.

Highly stereoselective synthesis of aryl/heteroaryl-C-nucleosides via the merger of photoredox and nickel catalysis.

A photoredox/nickel dual-catalyzed decarboxylative cross-coupling reaction of anomeric ribosyl/deoxyribosyl acids with aryl/heteroaryl bromides has been developed. The reaction proceeds smoothly under visible-light irradiation and features the using of cost-effective and easily handled catalysts and starting materials, which allows the highly stereoselective synthesis of diverse aryl/heteroaryl-C-nucleosides in moderate to high yields.

Pd-Catalyzed decarboxylative cross-coupling reactions of epoxides with α,β-unsaturated carboxylic acids.

A Pd-catalyzed decarboxylative cross-coupling of α,β-unsaturated carboxylic acids with cyclic and acyclic epoxides has been developed. Both β-monosubstituted and β-disubstituted unsaturated carboxylic acids, as well as conjugated diene unsaturated carboxylic acids are suitable reaction substrates. Substituted homoallylic alcohols were obtained in moderate to good yields. The product was obtained as a mixture of diastereomers favoring the anti diastereomer of the cyclic epoxides. This work provides a method for the modification of complex organic molecules containing α,β-unsaturated carboxylic acids.

New insight in Hiyama cross-coupling reactions: Decarboxylative, denitrogenative and desulfidative couplings

In this mini-review, recent advances and developments in the decarboxylative, denitrogenative, and desulfidative Hiyama-type cross-coupling reaction from 2011 up present are studied. This review focused mainly on mechanistic aspects of Hiyama cross-coupling reactions

Palladium-Catalyzed Cross-Coupling Reactions: A Powerful Tool for the Synthesis of Agrochemicals.

Pd-catalyzed cross-coupling reactions have become essential tools for the construction of carbon-carbon and carbon-heteroatom bonds. Over the last three decades, great efforts have been made with cross-coupling chemistry in the discovery, development, and commercialization of innovative new pharmaceuticals and agrochemicals (mainly herbicides, fungicides, and insecticides). In view of the growing interest in both modern crop protection and cross-coupling chemistry, this review gives a comprehensive overview of the successful applications of various Pd-catalyzed cross-coupling methodologies, which have been implemented as key steps in the synthesis of agrochemicals (on R&D and pilot-plant scales) such as the Heck, Suzuki, Sonogashira, Stille, and Negishi reactions, as well as decarboxylative, carbonylative, α-arylative, and carbon-nitrogen bond bond-forming cross-coupling reactions. Some perspectives and challenges for these catalytic coupling processes in the discovery of agrochemicals are briefly discussed in the final section. The examples chosen demonstrate that cross-coupling chemistry approaches open-up new, low-cost, and more efficient industrial routes to existing agrochemicals, and such methods also have the capability to lead the new generation of pesticides with novel modes of action for sustainable crop protection.

Synthesis of Aryl Alkynes via Copper Catalyzed Decarboxylative Alkynylation of 2-Nitrobenzoic Acids.

An efficient protocol for the synthesis of internal aryl alkynes was achieved via Cu-catalyzed decarboxylative cross-coupling reactions, and to the best of our knowledge, this is the first example of a Cu-catalyzed decarboxylative alkynylation of benzoic acids with terminal alkynes. This approach utilizes simple Cu salt as catalyst and O2, an abundant, clean, and green material, as the oxidant. The reaction tolerates various functional groups, and a variety of internal aryl alkynes were synthesized in 46-83% yields.

Synthesis of HIV NNRTI Doravirine Analogues via Visible-Light Photoredox Decarboxylative Cross-Coupling

A C(sp2)–C(sp3) decarboxylative cross-coupling reaction utilizing dual nickel and photoredox catalysis for rapid parallel synthesis of diverse C-ring analogues of the HIV NNRTI clinical candidate doravirine is developed and described herein. This protocol features an alkylation with readily available and inexpensive methyl bromoacetate followed by hydrolysis to prepare an advanced doravirine intermediate, which undergoes decarboxylative cross-coupling with a variety of aryl and heteroaryl bromides. The mildness, broad applicability, and sustainability of the current methodology are improvements over previously reported procedures and allow for rapid parallel synthesis of analogues. The optimization and scope of this method are reported.