Facilitating the transmetalation step with aryl-zincates in nickel-catalyzed enantioselective arylation of secondary benzylic halides

CF2H-synthon enables asymmetric radical difluoroalkylation for synthesis of chiral difluoromethylated amines

The difluoromethyl group is a crucial fluorinated moiety with distinctive biological properties, and the synthesis of chiral CF₂H-containing analogs has been recognized as a powerful strategy in drug design. To date, the most established method for accessing enantioenriched difluoromethyl compounds involves the enantioselective functionalization of nucleophilic and electrophilic CF₂H synthons. However, this approach is limited by lower reactivity and reduced enantioselectivity. Leveraging the unique fluorine effect, we design and synthesize a radical CF₂H synthon by incorporating isoindolinone into alkyl halides for asymmetric radical transformation. Here, we report an efficient strategy for the asymmetric construction of carbon stereocenters featuring a difluoromethyl group via nickel-catalyzed Negishi cross-coupling. This approach demonstrates mild reaction conditions and excellent enantioselectivity. Given that optically pure difluoromethylated amines and isoindolinones are key structural motifs in bioactive compounds, this strategy offers a practical solution for the efficient synthesis of CF₂H-containing chiral drug-like molecules.

Co-Catalyzed Suzuki-Miyaura Coupling of Organoboronic Acids and Alkynyl Chlorides Using Potassium Bicarbonate as Base

Organoboronic acids, some of the most common and widely used organoboron compounds, have not yet been used in the cobalt-catalyzed cross coupling reactions, despite cobalt demonstrating good reactivity with zinc reagents, Grignard reagents, and metal organoborates that are formed by n-butyl lithium or alkaline metal alkoxide salts and organoboron esters. Herein, a highly efficient and practical cobalt-catalyzed coupling reaction of aryl/alkenyl boronic acids and alkynyl chloride under mild reaction conditions is reported. The advantages of the organoboronic acids, along with a broad functional group compatibility and the reaction's tolerance to moisture and air, enable this reaction to be a synthetically useful protocol for the construction of a C(sp2)-C(sp) bond. Lastly, the synthesis of two natural products and a key intermediate of roxadustat was effectively accomplished using the methodology to construct the critical alkynyl-aryl bond.

Redox-neutral decarboxylative coupling of fluoroalkyl carboxylic acids via dual metal photoelectrocatalysis

Given the importance and beneficial characteristics of aliphatic CF3 chiral compounds in modern chemistry, efficient strategies for their synthesis are highly sought after. While α-CF3 carboxylic acid is an emerging and easily accessible CF3-containing synthon, its use as a source of fluoroalkyl is highly challenging due to its high oxidation potential. Herein, we disclose a photoelectrocatalytic method for the direct and enantioselective decarboxylative cross-coupling of α-CF3 carboxylic acids. Key to our approach is the strategic integration of the LMCT-induced decarboxylative process with classical nickel catalysis. This strategy enables the efficient synthesis of aliphatic chiral CF3 compounds with a broad range of substrates.

Redox-Active α-Amino-CF3 Reagents: Developing and Applications in Ni-Catalyzed Reductive Cross-Coupling

α-Amino-CF3 compounds are widely employed in bio- and pharmaceutical chemistry for improved stability and bioactivities. Traditional methods often face challenges with functional group tolerance and lack a general approach for late-stage functionalization. Herein, we report a new type of redox-active α-amino-CF3 reagents, easily prepared from trifluoro acetaldehyde hydrates. These α-amino-CF3 reagents can serve as versatile building blocks for coupling with alkynyl bromides, aryl bromides, and enol triflates under nickel catalysis.

Dual Nickel- and Photoredox-Catalyzed Asymmetric Reductive Cross-Couplings: Just a Change of the Reduction System?

ConspectusIn recent years, nickel-catalyzed asymmetric coupling reactions have emerged as efficient methods for constructing chiral C(sp3) carbon centers. Numerous novel approaches have been reported to rapidly construct chiral carbon-carbon bonds through nickel-catalyzed asymmetric couplings between electrophiles and nucleophiles or asymmetric reductive cross-couplings of two different electrophiles. Building upon these advances, our group has been devoted to interrogating dual nickel- and photoredox-catalyzed asymmetric reductive cross-coupling reactions.In our endeavors over the past few years, we have successfully developed several dual Ni-/photoredox-catalyzed asymmetric reductive cross-coupling reactions involving organohalides. While some probably think that this system is just a change of the reduction system from traditional metal reductants to a photocatalysis system, a question that we also pondered at the beginning of our studies, both the achievable reaction types and mechanisms suggest a different conclusion: that this dual catalysis system has its own advantages in the chiral carbon-carbon bond formation. Even in certain asymmetric reactions where the photocatalysis regime functions only as a reducing system, the robust reducing capability of photocatalysts can effectively accelerate the regeneration of low-valent nickel species, thus expanding the selectable scope of chiral ligands. More importantly, in many transformations, besides reducing nickel catalysts, the photocatalysis system can also undertake the responsibility of alkyl radical formation, thereby establishing two coordinated, yet independent catalytic cycles. This catalytic mode has been proven to play a crucial role in achieving diverse asymmetric coupling reactions with great challenges.In this Account, we elucidate our understanding of this system based on our experience and findings. In the Introduction, we provide an overview of the main distinctions between this system and traditional Ni-catalyzed asymmetric reductive cross-couplings with metal reductants and the potential opportunities arising from these differences. Subsequently, we outline various chiral carbon-carbon bond-forming types obtained by this dual Ni/photoredox catalysis system and their mechanisms. In terms of chiral C(sp3)-C(sp2) bond formation, extensive discussion focuses on the asymmetric arylations of α-chloroboronates, α-trifluoromethyl alkyl bromides, α-bromophosphonates, and so on. In the realm of chiral C(sp3)-C(sp) bond formation, asymmetric alkynylations of α-bromophosphonates and α-trifluoromethyl alkyl bromides have been presented herein. Regarding C(sp3)-C(sp3) bond formation, we take the asymmetric alkylation of α-chloroboronates as a compelling example to illustrate the great efficiency of this dual catalysis system. This summary would enable a better grasp of the advantages of this dual catalysis system and clarify how the photocatalysis regime facilitates enantioselective transformations. We anticipate that this Account will offer valuable insights and contribute to the development of new methodologies in this field.

Halogen-Atom Transfer Enabled Catalytic Enantioselective Coupling to Chiral Trifluoromethylated Alkynes via Dual Nickel and Photocatalysis

With halogen-atom transfer as an effective tool, a novel catalytic enantioselective protocol to generate chiral trifluoromethylated alkynes has been established by a cooperative photoredox and nickel catalysis system, providing a straightforward and modular route to access this type of product in good yields and enantioselectivities. The halogen-atom transfer process is essential for the reaction and this novel strategy offers another promising way to utilize alkyl halides with highly negative reduction potentials. It firstly expands nickel-catalyzed asymmetric reductive cross-couplings of organohalides from the traditional single-electron transfer to halogen-atom transfer.

Enantioselective Construction of C-SCF3 Stereocenters via Nickel Catalyzed Asymmetric Negishi Coupling Reaction

The construction of the SCF3-containing 1,1-diaryl tertiary carbon stereocenters with high enantioselectivities is reported via a nickel-catalyzed asymmetric C-C coupling strategy. This method demonstrates simple operations, mild conditions and excellent functional group tolerance, with newly designed SCF3-containing synthon, which can be easily obtained from commercially available benzyl bromide and trifluoromethylthio anion in a two-step manner. Further substrate exploration indicated that the reaction system could be extended to diverse perfluoroalkyl sulfide (SC2F5, SC3F7, SC4F9, SCF2CO2Et)-substituted 1,1-diaryl compounds with excellent enantioselectivities. The synthetic utility of this transformation was further demonstrated by convenient derivatization to optical SCF3-containing analogues of bioactive compounds without an apparent decrease in enantioselectivity.

SCpRh(III)-Catalyzed Asymmetric C-H Trifluoromethylalkylation of N-Methoxybenzamides with β-Trifluoromethyl-α,β-Unsaturated Ketones

Asymmetric C-H trifluoromethylalkylation represents a novel and straightforward synthetic method for the construction of chiral CF3-containing compounds. However, the reported examples remain limited, given the challenges of reactivity and enantioselective control. Herein, we report a SCpRh(III)-catalyzed asymmetric aryl and alkenyl C-H trifluoromethylalkylation reaction with β-trifluoromethyl-α,β-unsaturated ketones. The chiral CF3-bearing adducts were obtained in moderate to good yields with high enantioselectivity (up to 81% yield and 96% ee). The reaction features mild conditions and broad substrate scope. The chiral CF3-bearing products could undergo diverse functional group transformations.

Metal-Catalyzed Enantioconvergent Transformations

Enantioconvergent catalysis has expanded asymmetric synthesis to new methodologies able to convert racemic compounds into a single enantiomer. This review covers recent advances in transition-metal-catalyzed transformations, such as radical-based cross-coupling of racemic alkyl electrophiles with nucleophiles or racemic alkylmetals with electrophiles and reductive cross-coupling of two electrophiles mainly under Ni/bis(oxazoline) catalysis. C-H functionalization of racemic electrophiles or nucleophiles can be performed in an enantioconvergent manner. Hydroalkylation of alkenes, allenes, and acetylenes is an alternative to cross-coupling reactions. Hydrogen autotransfer has been applied to amination of racemic alcohols and C-C bond forming reactions (Guerbet reaction). Other metal-catalyzed reactions involve addition of racemic allylic systems to carbonyl compounds, propargylation of alcohols and phenols, amination of racemic 3-bromooxindoles, allenylation of carbonyl compounds with racemic allenolates or propargyl bromides, and hydroxylation of racemic 1,3-dicarbonyl compounds.

Visible-Light-Induced Nickel-Catalyzed Radical Cross-Couplings to Access α-Aryl-α-trifluoromethyl Alcohols

A photochemically induced nickel-catalyzed radical cross-coupling of phthalimido trifluoroethanol with aryl bromides to furnish α-aryl-α-trifluoromethyl alcohols is reported. This reaction proceeds via a photoinduced charge transfer of an electron donor-acceptor complex between Hantzsch ester and phthalimido trifluoroethanol, followed by 1,2-hydrogen atom transfer, to generate the α-hydroxytrifluoroethyl radical for the cross-coupling of aryl bromides. No exogenous photocatalysts or stoichiometric metal reductants are required in this mild and operationally simple protocol. Broad substrate compatibility and excellent functional group tolerance are observed.

Enantioselective Radical Trifluoromethylation of Benzylic C-H Bonds via Cooperative Photoredox and Copper Catalysis

The first enantioselective radical trifluoromethylation of benzylic C-H bonds has been established by a cooperative photoredox and copper catalysis system, providing straightforward access to structurally diverse benzylic trifluoromethylation products in good yields with excellent enantioselectivities under mild conditions. Our method features a broad substrate scope and excellent functional group compatibility. Merging the cooperative photoredox catalysis with copper catalysis is essential for the reaction, where the photoredox catalysis is used for the generation of benzylic radicals from alkyl arenes through a hydrogen atom transfer process and the copper catalysis is used for the enantioselective trifluoromethylation of the benzylic radicals.

Copper-Catalyzed Stereospecific Transformations of Alkylboronic Esters

Copper-catalyzed stereospecific cross-couplings of boronic esters are reported. Boron "ate" complexes derived from pinacol boronic esters and tert-butyl lithium undergo stereospecific transmetalation to copper cyanide, followed by coupling with alkynyl bromides, allyl halides, propargylic halides, β-haloenones, hydroxylamine esters, and acyl chlorides. Through this simple transformation, commercially available inexpensive compounds can be employed to convert primary and secondary alkylboronic esters to a wide array of synthetically useful compounds.

Nickel-Catalyzed Cross-Coupling of Acyl Chloride with Racemic α-Trifluoromethyl Bromide to Access Chiral α-Trifluoromethyl Ketones

The nickel-catalyzed reductive cross-coupling reaction of acyl chloride with racemic secondary α-trifluoromethyl bromide has been developed. By this chemistry, a series of structurally interesting chiral α-CF₃ carbonyl compounds could be accessed with great enantioselectivity and good functional group tolerance. The study of late-stage transformation indicated that this chemistry could be used as the robust method to prepare products that contain a bioactive motif. Furthermore, the importance of the α-trifluoromethyl group to this reaction has been illustrated by control experiments.

Catalytic Asymmetric Construction of CF3-Substituted Chiral sp3 Carbon Centers

Due to the unique steric and electronic nature of the fluorine atom, organofluorine compounds have received significant attention in the fields of pharmaceuticals and agrochemicals. In particular, the CF3 group is frequently found in biologically active compounds. However, compared to aryl- and alkenyl-CF3-containing molecules, the construction of sp3 carbon-based alkyl-CF3-containing molecules, particularly via catalytic enantioselective synthesis, remains a considerable challenge in spite of their high potential in medicinal applications. This short review focuses on recent advances in this research area, and the reported strategies are categorized according to reaction types and starting substrates. In addition, chiral catalysts, substrate scope, and reaction mechanisms are briefly summarized.

1 Introduction

2 Stereoselective Introduction of a CF3 Group

2.1 Nucleophilic Addition to Carbonyls and Imines

2.2 Electrophilic Substitution at the α Position of Carbonyls

2.3 Allylic Nucleophilic Substitution

3 Stereoselective Functionalization of CF3-Substituted Molecules

3.1 Electrophilic Substitution of α-CF3 Carbonyls

3.2 Substitution of α-Halo CF3 Compounds

3.3 Addition-Type Reactions with CF3-Substituted Alkenes

4 Conclusion and Outlook

Enantioselective Synthesis of Secondary β-Trifluoromethyl Alcohols via Catalytic Asymmetric Reductive Trifluoroalkylation and Diastereoselective Reduction

Fluorinated motifs are frequently encountered in drugs and agrochemicals. Incorporating fluorine-containing motifs in drug candidates for lead optimization in pharmaceutical research and development has emerged as a powerful tool. The construction of molecules that feature a trifluoromethyl (CF₃-) group on a stereogenic carbon has accumulated broad research efforts. Unlike its well-explored, biologically active methyl counterpart, asymmetric construction of β-trifluoromethylated alcohols bearing adjacent stereocenters still remains elusive. Through retrosynthetic analysis, we posited that followed by sequential reduction of carbonyl, the initial construction of chiral α-trifluoromethylated ketones could render the desired product in a facile, one-pot fashion. Herein, we developed the first example of nickel-catalyzed asymmtric reductive cross-coupling trifluoroalkylation of acyl chlorides for enantioselective synthesis of diverse α-trifluoromethylated ketones. The one-pot reduction of these α-trifluoromethylated ketones furnished corresponding alcohols bearing β-CF₃-substituted stereogenic carbons with excellent diastereoselectivity and complete enantioselective retention. High yields/enantioselectivity, mild conditions, and good functional group compatibility are shown in the system. Utilities of the method are also illustrated by applying asymmetric, late-stage trifluoroalkylation of biologically active complex molecules, revealing tremendous potential for development of CF₃-containing chiral drugs.

Organometallic catalysis under visible light activation: benefits and preliminary rationales

Organometallic catalysis under visible light activation is an emerging field. Activation by photosensitization or by direct light absorption of organometallic complexes can facilitate or trigger elementary steps in a catalytic cycle such as pre-catalyst reduction, oxidative addition, transmetalation and reductive elimination, as well as the ability of generating radical intermediates, widening the structural diversity offered by classical couplings. This perspective aims to highlight key examples of these light-induced or enhanced processes, with an emphasis on the underlying mechanisms involved.

Diverse Synthesis of Chiral Trifluoromethylated Alkanes via Nickel-Catalyzed Enantioconvergent Reductive Hydroalkylation of Unactivated Olefins

Here, we report a nickel-catalyzed enantioconvergent hydroalkylation of olefins with trifluoromethyl-containing α-alkyl halides for the synthesis of enantioenriched trifluoromethylated alkanes. This reaction employs readily available and bench-stable alkenes as alkyl coupling partners, featuring mild conditions, a broad substrate scope, and high functional group tolerance. The synthetic utility of this method is further demonstrated in the late-stage functionalization of a range of drug molecules and natural products.

Transmetalation of boronic acids and their derivatives: mechanistic elucidation and relevance to catalysis

The Suzuki-Miyaura reaction (the cross-coupling reaction of boronic acids with organic halides catalysed by Pd complexes) has been recognised as a useful synthetic organic reaction that forms a C(sp²)-C(sp²) bond. The catalytic cycle of the reaction involves the transmetalation of aryl- and alkenylboronic acids with Pd(II) complexes. It migrates the aryl and alkenyl groups of boronic acid to Pd and produces a Pd-C bond. Many studies have investigated the mechanism of transmetalation. They elucidated the mechanism of the organometallic reaction and its role as a fundamental step in catalytic reactions. This perspective reviews studies on the transmetalation of aryl- and alkenylboronic acids with Pd(II) complexes. Emphasis was laid on the structures and chemical properties of the intermediate Pd complexes and the effects of OH^- on the pathways of the catalytic Suzuki-Miyaura reaction. The reactions of arylboronic acids with Rh(I)-OH complexes were investigated, which are relevant to the mechanism of Rh-catalysed addition of aryl boronic acids to enones and aldehydes. Recent studies on the transmetalation of boronic acids with other late transition metals such as Fe(II), Co(I), Pt(II), Au(III), and Au(I) are presented with the related catalytic reactions and their utilisation in the synthesis of aromatic molecules and π-conjugated materials.

Iridium-catalyzed enantioselective addition of an N-methyl C-H bond to α-trifluoromethylstyrenes via C-H activation

The Ir-catalyzed enantioselective addition of an N-methyl C-H bond of 2-(methylamino)pyridine derivatives to α-trifluoromethylstyrenes proceeded via C-H activation to give chiral γ-branched amine derivatives having a trifluoromethyl-substituted stereocenter. It was found that a bulky and electron-withdrawing group at the 3-position of 2-(methylamino)pyridines was necessary for the present C-H addition reaction catalyzed by a cationic iridium/chiral bisphosphine complex.

Transition Metal-Catalyzed Cross-Couplings of Benzylic Sulfone Derivatives

In recent years, the use of organosulfones as a new class of cross-coupling partner in transition-metal catalyzed reactions has undergone significant advancement. In this personal account, our recent investigations into desulfonylative cross-coupling reactions of benzylic sulfone derivatives catalyzed by Pd, Ni, and Cu catalysis is described. Combined with the facile α-functionalizations of sulfones, our methods can be used to form valuable multiply-arylated structures such as di-, tri-, and, tetraarylmethanes from readily available substrates. The reactivity of sulfones can be increased by introducing electron-withdrawing substituents such as 3,5-bis(trifluoromethyl)phenyl and trifluoromethyl groups, which enable more challenging cross-coupling reactions. Reactive intermediates including Cu-carbene complexes were identified as key intermediates in sulfone activation, representing new types of C-SO₂ bond activation processes. These results indicate sulfones are powerful functional groups, enabling new catalytic desulfonylative transformations.

Copper-Catalyzed Highly Selective Protoboration of CF3 -Containing 1,3-Dienes

The copper-catalyzed highly selective protoboration of CF₃ -containing conjugated diene with proton source and B₂ Pin₂ has been developed. This chemistry could suppress the well-known defluorination and provide borated reagents with an intact CF₃ -group. Further studies indicated that the functional group tolerance of this chemistry is very well, and the products could be used as versatile precursors for different types of transformations. Importantly, using chiral diphosphine ligand, we have developed the first example for using such starting material to synthesis allylic boron-reagents which bearing a CF₃ -containing chiral center. Notably, the reaction mechanism was intensively studied by DFT calculations, which could reveal the reason that defluorination was inhibited.

Dual Nickel- and Photoredox-Catalyzed Reductive Cross-Coupling to Access Chiral Trifluoromethylated Alkanes

A dual nickel/photoredox-catalyzed enantioselective reductive cross-coupling of aryl halides with CF₃-substituted racemic alkyl electrophiles has been established. The approach accommodates a broad palette of aryl iodides and alkyl bromides to access a variety of chiral CF₃-containing compounds. The exceptionally mild conditions (visible light, ambient temperature, no strong base) and no need for Grignard reagents or stoichiometric metallic reductants provide this transformation huge potential in the application of the late-stage functionalization of complex molecules.

Synthesis of difluoromethylated diarylmethanes via Fe(OTf)3-catalyzed Friedel-Crafts reaction of 2,2-difluoro-1-arylethyl phosphates

The Fe(OTf)₃-catalyzed Friedel-Crafts reaction of 2,2-difluoro-1-arylethyl phosphates with electron-rich (hetero)arenes afforded difluoromethylated diarylmethanes. Control experiments showed that Fe(OTf)₃ behaves as the Lewis acid, and that the phosphate leaving group and o- or p-alkoxy substituents on the substrates are necessary for the Fe(OTf)₃-catalyzed reaction to proceed under mild conditions.

Diverse Synthesis of Chiral Trifluoromethylated Alkanes via Nickel-Catalyzed Asymmetric Reductive Cross-Coupling Fluoroalkylation

The trifluoromethyl group represents one of the most functional and widely used fluoroalkyl groups in drug design and screening, while the drug candidates containing chiral trifluoromethyl-bearing carbons are still few due to the lack of efficient methods for the asymmetric introduction of trifluoromethyl group into organic molecules. Herein, we described a nickel-catalyzed asymmetric trifluoroalkylation of aryl iodides, for the first time, by utilizing reductive cross-coupling in enantioselective fluoroalkylation. This novel method has demonstrated high efficiency, mild conditions, and excellent functional group tolerance, especially for substrates containing diverse pharmaceutical and bioactive molecules moieties. This strategy provided an efficient and facile way for diversity-oriented synthesis of chiral trifluoromethylated alkanes.

Synthesis of Chiral α-CF3-Substituted Benzhydryls via Cross-Coupling Reaction of Aryltitanates

We describe a highly efficient approach toward α-CF₃-substituted benzhydryls thanks to the employment of organotitanium(IV) based nucleophiles. The use of commercially available anesthetic halothane as a cheap fluorinated building block in a sequential one-pot nickel-catalyzed enantioselective cross-coupling reaction of aryl titanates allowed for the synthesis of chiral α-CF₃-substituted benzhydryls in good yields and excellent enantioselectivities. Alternatively, α-CF₃-benzyl bromides could be employed under similar conditions to obtain the same family of compounds in higher yields and excellent selectivities. A benzhydryl moiety is a common motif in many biologically active compounds, and their enantioenriched fluorinated analogs should be of great interest in the search for novel drugs and agrochemicals.

Generation of Carbocations under Photoredox Catalysis: Electrophilic Aromatic Substitution with 1-Fluoroalkylbenzyl Bromides

A novel Friedel-Crafts-type alkylation of arenes to access valuable 1-fluoroalkyl-1,1-biaryl compounds is established under mild conditions. The key to success is the efficient generation of a destabilized benzylic carbocation intermediate via two consecutive single-electron transfer processes by virtue of visible-light photoredox catalysis. This unique activation pattern avoids using strong Lewis acids and high temperatures that are required for generation of destabilized carbocations in traditional Friedel-Crafts reactions. This protocol demonstrates the first example of photoredox-catalyzed heterolysis of electronically deactivated benzylic C-Br bonds for the formation of destabilized carbocation intermediates.

Copper-Catalyzed Enantioconvergent Radical Suzuki-Miyaura C(sp3)-C(sp2) Cross-Coupling

A copper-catalyzed enantioconvergent Suzuki-Miyaura C(sp³)-C(sp²) cross-coupling of various racemic alkyl halides with organoboronate esters has been established in high enantioselectivity. Critical to the success is the use of a chiral cinchona alkaloid-derived N,N,P-ligand for not only enhancing the reducing capability of copper catalyst to favor a stereoablative radical pathway over a stereospecific S_N2-type process but also providing an ideal chiral environment to achieve the challenging enantiocontrol over the highly reactive radical species. The reaction has a broad scope with respect to both coupling partners, covering aryl- and heteroarylboronate esters, as well as benzyl-, heterobenzyl-, and propargyl bromides and chlorides with good functional group compatibility. Thus, it provides expedient access toward a range of useful enantioenriched skeletons featuring chiral tertiary benzylic stereocenters.

Selective Quadruple C(sp3)-F Functionalization of Polyfluoroalkyl Ketones

The significance of organofluorine compounds has inspired the establishment of numerous methods for the functionalization of rather inert C-F bonds. Despite advances achieved in the manipulation of C(sp²)-F bonds by employing transition-metal catalysts, such as Pd, Rh, Cu, Ni, Ru, and Ir, strategies that address the paucity of effective pathways for selective activation of multiple C(sp³)-F bonds remained challenging. In this context, we present an unprecedented coupling-aromatization-cyclization reaction of polyfluorinated ketones with diverse N- and S-nucleophiles that forms regiodefined perfluoroalkylated naphtho[1,2-b]furan/benzofuran derivatives by harnessing Co-promoted distinctive quadruple C(sp³)-F bonds cleavage relay. This chemistry involving controlled and successive selective defluorination at heteronuclear centers would greatly contribute to the preparation of drug-like heterocycles as well as the late-stage elaboration of biorelevant compounds. Controlled experiments and DFT theoretical studies revealed that the combination of cheap cobalt salt with Cs₂CO₃ enable expeditious C-F functionalization.

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First example of consecutive selective quadruple C(sp³)-F functionalization

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Selectively and controllably partial defluorination at heteronuclear sites

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Conversion to value-added chemicals by using polyfluorocarbons and nucleophiles

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DFT calculations were performed to support mechanistic proposal

Cobalt-Catalyzed Asymmetric Cross-Coupling Reaction of Fluorinated Secondary Benzyl Bromides with Lithium Aryl Boronates/ZnBr2

A cobalt-catalyzed asymmetric cross-coupling of α-bromo-α-fluorotoluene derivatives with a variety of aryl zincates derived from lithium aryl n-butyl pinacol boronates and ZnBr₂ under mild reaction conditions was described. In addition to mild reaction conditions, another advantage includes the compatibility of various common functional groups such as fluoride, chloride, bromide, cyano, or ester groups. Furthermore, this protocol was successfully applied to the enantioselective synthesis of three fluorinated derivatives of biologically active compounds or drug molecules.

Synthesis and characterization of nitrogen-based ionic liquids bearing allyl groups and examples of their application

The synthesis and characterization of a series of allyl-functionalized ionic liquids and examples of their application in catalysts and surface-functionalizing compound formation.

Palladium-catalyzed selective defluorinative sulfenylation for the synthesis of fluorovinylthioethers

An efficient transformation of trifluoromethylated benzyl bromides to monofluoroalkenes through Pd-catalyzed selective defluorinative sulfenylation is described.