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CuI/6-hydroxy picolinohydrazide-catalyzed coupling of (hetero)aryl chlorides with anilines proceeded well at 100 °C to afford biaryl amines in a diverse manner, which represents the first example of Cu-catalyzed biaryl amines under milder conditions. The same catalytic system could make the coupling of (hetero)aryl bromides with anilines work at room temperature, giving the corresponding products with an excellent reaction scope.

A gold(I)-catalyzed cyclization of enynone-nitriles with amines to 2,3-DHPs assisted by La(OTf) 3 has been developed. The compatibility with abundant nucleophiles, high functional group tolerance, rapid assembly of molecular complexity, and late-stage functionalization of bioactive substances make this approach attractive for the construction of 2,3-DHPs, which have rarely been synthesized in the literature. The reaction proceeds via cascade cyclization involving gold/Lewis acid cooperative activation of the alkene and the cyano moiety.

We report herein that nickel-mediated trifluoromethylation of chlorinated and brominated phenol derivatives ClArOTs and BrArOTf gave chloro(bromo)trifluoromethylarenes through the chemoselective cleavage of Ar-O bonds. Furthermore, under similar reaction conditions, the chemoselective trifluoromethylation of Ar-Cl and Ar-Br bonds of ClArOPiv and BrArOTs was achieved to give trifluoromethylated phenol derivatives.

The fluorosulfonyldifluoromethylation of unactivated alkenes and (hetero)arenes with iododifluoromethanesulfonyl fluoride (ICF 2 SO 2 F) under visible light photoredox catalysis was successfully developed. Key to the successful fluorosulfonyldifluoromethylation of aromatic compounds was the usage of AgOTf as an additive to promote the formation of the CF 2 SO 2 F radical. The protocol provided a straightforward way to introduce the interesting and useful CF 2 SO 2 F group on sp 3 and sp 2 carbons.

A copper-catalyzed arylation or alkenylation of quinoline N -oxides with aryl- or alkenylboronates, respectively, has been developed, which provides an efficient route for C2-substituted oxygenated quinolines under mild reaction conditions. The reaction shows a broad substrate scope for both quinoline N -oxides and aryl/alkenylboronates, mild reaction conditions, and high reaction efficiency. The formation of an aryl- or alkenyl-copper species as the key intermediate was suggested to be involved in this reaction.

Herein we report a photoredox/nickel-catalyzed cross-coupling of aryl bromides with 1,1,1,3,3,3-hexafluoroisopropanol for the construction of hexafluoroisopropyl aryl ethers. The mild reaction conditions employed allow for the applicability of a wide range of aryl and heteroaryl bromides. Late-stage functionalization and preliminary mechanistic studies have been demonstrated.

A gold-catalyzed cycloaddition/ring opening of allenamides with quinoline N -oxides has been developed, which provides C2-alkenylated quinolines with high E selectivity in moderate to high yields. It is noted that quinoline N -oxides with a C8 or C7 substituent are crucial for this catalytic reaction.

Esters are bulk and fine chemicals and ubiquitous in polymers, bioactive compounds, and natural products. Their traditional synthetic approach is the esterification of carboxylic acids or their activated derivatives with alcohols. Herein, a bimetallic relay catalytic protocol was developed for the aerobic esterification of one alcohol in the presence of a slowly oxidizing alcohol, which has been identified as methanol. A concise synthesis of phlomic acid was executed to demonstrate the practicality and potential of this reaction.

Enantioselective construction of all-carbon quaternary centers has been achieved via the palladium-catalyzed highly enantioselective allenylation of oxindoles with 2,3-allenylic carbonates to afford a variety of optically active allene products, which contain oxindole units with different functional groups, in high ee. The corresponding synthetic applications have also been demonstrated.

A nickel-catalyzed direct reaction of allylic alcohols with easily accessible alkenyl boronates has been developed, which provides valuable 1,4-dienes with high regio- and stereoselectivity in good to excellent yields, wide substrate scope, and functional group compatibility. The catalytic system simply consists of Ni(cod) 2 as the catalyst and a ligand, without a need for a base and alcohol activator in most cases. The proper choice of ancillary ligands is highly important for this reaction. Depending on the substitution pattern of allylic alcohols and/or alkenyl boronates, different ligands were used for improving the reaction efficiency.

A gold-catalyzed oxidative cyclization/nucleophilic addition/C-C bond cleavage reaction of ynones with various nucleophiles has been developed. This methodology allows for the formation of highly functionalized linear N -Ts amides with broad substrate scope, high efficiency, and general tolerance of functional groups. A wide range of nucleophiles such as alcohols, water, and amines including aryl and alkyl amines are compatible with the current method. The C-C triple bond cleavage of the ynone substrate was observed during the process.

A five-membered N-O heterocycle, 4,5-dihydro-1,2,4-oxadiazole, was found to act as a single nitrogen atom transfer reagent via elimination of a ketone/aldehyde and a nitrile. This reagent was successfully applied for the synthesis of isoxazoles from ynones promoted by Sc(OTf) 3 or through Au(I)/Sc(OTf) 3 synergistic catalysis. The efficiency of this protocol was also demonstrated by its application in modifications of structurally complex natural products and pharmaceuticals.

An efficient photoredox/nickel dual-catalyzed coupling of allyl trifluoroborates with aryl halides has been developed, which provides an attractive route to diverse-substituted allylic benzenes. The method offers several advantages, such as high efficiency and regioselectivity, mild reaction conditions, wide substrate scope, and functional group compatibility. Mechanistic studies suggest that a π-allyl nickel(III) intermediate generated via the addition of an allyl radical to nickel species is possibly formed as a key reaction intermediate.

A catalytic defluorinative boroarylation of alkenes with polyfluoroarenes and B 2 pin 2 with the assistance of a PCy 3 -ligated copper catalyst was developed. Taking advantage of bench-stable alkenes as latent nucleophiles and avoiding traditional reliance on stoichiometric quantities of organometallics, this method showcased good functional group compatibility and proceeded under very mild reaction conditions. A series of valuable boronate-containing polyfluoroarenes including all-carbon quaternary carboncenter-containing triaryl alkylboronates that are otherwise difficult to access were efficiently prepared.

A nickel-catalyzed direct reaction of allylic alcohols with benzyl nitrile derivatives has been developed. The method provides an efficient route for the synthesis of nitriles bearing an α-tertiary or quaternary carbon center in good to excellent yields with high regioselectivity, wide substrate scope, and functional group compatibility. BSA was identified as the effective additive for facilitating the coupling process mainly for alkyl allylic alcohols.

A copper-catalyzed trifluoromethylation of (hetero)arylboronic acid pinacol esters with YlideFluor for the preparation of trifluoromethylated (hetero)arenes was described. The reaction conditions are mild and compatible with a broad range of functional groups. Heteroaryl boronic acid pinacol esters could also be trifluoromethylated in high yields. Application of this protocol for trifluoromethylation of drug and OLED molecules was demonstrated.

The first hydrofluoromethylation of unactivated alkenes with fluoroiodomethane and hydrosilanes is developed by merging photoredox catalysis and silane-mediated deiodination processes. The key to the success of this reaction is the use of water as the solvent to enhance the activity of CH 2 F radical toward unactivated alkenes.

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.

trans -Trifluoromethyltetrafluorosulfanyl chloride ( trans -CF 3 SF 4 Cl) is a unique reagent for the incorporation of the CF 3 SF 4 group into organic compounds. However, CF 3 SF 4 Cl was prepared from hazardous reagents or formed as mixture of trans and cis isomers in low yield. Herein, a silver-promoted selective synthesis of trans -CF 3 SF 4 Cl under safe gas-reagent-free conditions is described. Furthermore, the synthetic application of trans -CF 3 SF 4 Cl is demonstrated through the new trifluoromethyltetrafluorosulfanylation of α-diazo carbonyl compounds.

Pd-catalyzed intermolecular asymmetric allylic dearomatization of substituted β-naphthol derivatives with Boc-protected Morita-Baylis-Hillman (MBH) adducts was developed. The reaction occurs smoothly in 1,4-dioxane at room temperature in the presence of [Pd(C 3 H 5 )Cl] 2 (2.5 mol %), ( S , S p )-PHOX ligand (5.5 mol %), and Li 2 CO 3 (1.0 equiv). A series of dearomatized products were afforded in moderate to excellent yields and enantioselectivity (up to 99% yield, 97% ee). Furthermore, the compatibility with gram-scale reaction and mild conditions make the current method synthetically useful.

A rapid construction of enantioenriched benzofurochromanes was developed by SaBOX/copper(II) catalyzed enantioselective [3 + 2] annulation of γ-chromenes with quinones. This process takes advantage of the simple starting materials and a highly efficient chiral SaBOX/copper(II) catalyst system, leading to a variety of benzofurochromanes in up to 96% yield with up to 97% ee.

The Rh(III)-catalyzed highly enantioselective C2-arylation of indole derivatives with 1-diazonaphthoquinones is reported. In the presence of 2.5 mol % SCpRh complex and 20 mol % AgNO 3 , the C2-arylation reactions of indoles proceeded smoothly, affording a wide range of C2-arylated indole atropisomers in good yields and enantioselectivity (≤96% yield, ≤97% ee) under mild conditions. The method displays a broad substrate scope and good functional group tolerance.

Herein, chiral Brønsted acid-catalyzed intramolecular asymmetric allylic alkylation of indoles with allylic primary alcohols is described. The allyl alcohols were directly employed as the allylic precursors in this metal-free protocol, without preactivation or any additional activating reagents. This method provides the convenient synthesis of a broad range of functionalized tetrahydrocarbazoles in excellent yields (≤97%) with good enantioselectivity (≤93% ee). The optimal conditions are compatible for gram-scale reaction.

A straightforward synthesis of pyrimidines via Au(III) or Au(I)/Lewis-acid-catalyzed cascade reactions of propargyl alcohols with 3-amino-benzo[ d ]isoxazoles is described. The propargyl amine intermediates are readily generated in situ via oxophilic activation of gold(III) or a Lewis acid, which undergo cyclization/1,2-group migration/aromatization to deliver the desired products. Highly selective 1,2-H or -R 1 migrations are observed in most cases, and the migratory aptitude is dependent on the steric and electronic properties of the propargylic groups.

A gold-catalyzed cyclization of conjugated ynones with various nucleophiles such as indoles, alcohols, and thiols has been developed. The reaction provides a new and efficient protocol for the synthesis of functionalized pyrroles with wide versatility and functional group compatibility. Remarkably, for indolyl, alkoxy, or sulfenyl pyrroles, all could be constructed efficiently by this single methodology. In addition, cis -hydrofunctionalizations of ynones are involved in these reactions.

Pd-catalyzed asymmetric dearomative arylation of C3-substituted indoles is realized via a desymmetrization strategy. A BINOL-derived chiral phosphoramidite ligand is found to be highly efficient for the stereoselective control in this reaction. This method provides a convenient synthesis of spiroindolenines bearing two stereogenic centers in good yields (up to 98%) with excellent diastereo- and enantioselectivities (up to >20:1 dr and 97% ee), which could also be applied in asymmetric dearomative arylation of the simple C3-tethered indoles.

N , N '-Bis(pyridin-2-ylmethyl)oxalamide (BPMO) was found to be an apposite promoter for the Cu-catalyzed N -arylation of oxazolidinones and primary and secondary amides with (hetero)aryl iodides at room temperature. Excellent chemoselectivity reached between aryl iodides and aryl bromides, and a wide range of functional groups tolerated the reaction conditions, which led to the formation of greatly diverse N -arylation products.

A rhodium-catalyzed asymmetric oxidative C-H/C-H cross-coupling reaction between 1-aryl isoquinolines and indolizines is disclosed. With a matched pair of SCpRh complex and chiral carboxylic acid, enantioselective two-fold C-H/C-H cross-coupling reactions between 1-aryl isoquinolines and indolizines provide a variety of axially chiral bi(hetero)aryls in excellent yields and enantioselectivity (up to 96% yield and 98% ee). Mechanistic studies suggest that both C-H cleavages are likely reversible.

A palladium catalyzed carbonylative cross-coupling of difluoroalkyl halides with alkyl-9-BBN under 1 atm of CO has been developed. The reaction shows broad substrate scope and high functional group tolerance, even toward complex pharmaceuticals, providing a general and straightforward method to access alkyldifluoroalkyl ketones. Preliminary mechanistic studies reveal that a radical pathway is involved in the reaction.

A nickel-catalyzed highly regioselective addition/cyclization of ynamide-benzylnitriles with organoboronic acids has been developed. The reaction offers an attractive route for the construction of diamino-functionalized 1-arylnaphthalenes, which is difficult to synthesize by other methods. In addition, a wide range of functional groups are tolerated in this reaction.

A multicomponent strategy for the synthesis of functionalized furan-3-carboxylates based on gold-catalyzed oxidative cyclization of diynones with alcohols or water has been developed. Mechanistic studies revealed that a rare nucleophilic attack to the carbonyl group of the α,α'-dioxo gold carbene instead of the carbene center and 1,2-alkynyl group migration were involved in this transformation. This method offers several advantages such as mild conditions, high regio- and chemoselectivity, and wide functional group compatibility.

An efficient nickel(0)-catalyzed addition of benzyl nitriles to terminal vinyl ketones via C(sp 3 )-H functionalization has been developed. The reaction provides a novel and efficient protocol for the synthesis of α-functionalized benzyl nitriles with a wide range of structural diversity under mild reaction conditions while obviating the use of a strong base. The work might be potentially useful toward the development of an enantioselective variant using chiral nitrogen ligands.

An efficient synthesis of halogen-substituted allenyl ketones via Ag-catalyzed oxidative ring opening of allenyl cyclic alcohols under mild reaction conditions has been achieved. The reaction features a wide substrate scope and excellent regioselectivity. The synthetic potential of the products has been demonstrated by their conversion to stereodefined alkenes and heterocyclic compounds.

Reported herein is a direct and efficient route to 1-bromo-1-fluoroalkanes through the reaction of unactivated alkenes with dibromofluoromethane under photoredox catalysis. The key to the success of these addition reactions is the employment of a suitable photoredox catalyst. In particular, hydro- and bromo-bromofluoromethylated products were chemoselectively formed using THF and DMF/H 2 O as solvents, respectively. Furthermore, the synthetic application of the prepared 1-bromo-1-fluoroalkanes has been demonstrated by their transformation into a variety of fluorine-containing compounds.

A highly regioselective nickel/Lewis acid catalyzed amination/cyclization of ynamide-nitriles with amines involving β-addition has been developed. The reaction offers an attractive and efficient route for the synthesis of 3-aminoindoles and 4-aminoisoquinoline derivatives. The Ts-group on the ynamide acts as a directing group to produce the alkenyl nickel species with high regioselectivity.

Electrochemically driven, Cp*Ir(III)-catalyzed regioselective annulative couplings of benzoic acids with alkynes have been established herein. The combination of iridium catalyst and electricity not only circumvents the need for stoichiometric amount of chemical oxidant, but also ensures broad reaction compatibility with a wide array of sterically and electronically diverse substrates. This electrochemical approach represents a sustainable strategy as an ideal alternative and supplement to the oxidative annulations methodology to be engaged in the synthesis of isocoumarin derivatives.

A nickel-catalyzed reductive cross-coupling between industrial chemical CF 3 CH 2 Cl and (hetero)aryl bromides and chlorides has been reported. The reaction is synthetically simple without the preparation of arylmetals and exhibits high functional group tolerance. The utility of this protocol has been demonstrated by the late-stage modification of pharmaceuticals, providing a facile route for medicinal chemistry.

A gold-catalyzed cyclization of aniline-tethered furan-ynones has been developed. The reaction proceeds via trapping of the resulting stabilized cationic intermediate with an amide group leading to polycycles featured with a spiro-cyclohexadienone-hydrofuran framework with high efficiency. The resulting N -alkyl products undergo photorearrangements to afford the ring-enlarged benzo[ b ]azepine derivatives or iron-promoted novel rearrangement to diketone-containing spirocycles involving multiple C-X bond cleavages and formations.

The palladium-catalyzed asymmetric [4 + 3] cycloaddition of a sulfonyl-trimethylenemethane (TMM) donor with azadienes furnished various sulfonyl-fused azepines with exclusive regioselectivities and excellent stereoselectivities (up to >20:1 dr, >99% ee) in high yields (up to 93%). Moreover, sulfone, serving as a transient activating group of the TMM species, can be easily removed from the cycloadducts to provide the structurally simple fused azepines with excellent enantioselectivities. This strategy demonstrates sulfonyl-TMM as an effective surrogate of naked TMM with high reactivity, exclusive regioselectivity, and excellent stereoselectivity.

The first copper and zinc copromoted trifluoromethylation using trifluoromethanesulfonic anhydride (Tf 2 O) as a trifluoromethylating reagent has been developed. The reaction of alkenes or alkynes with Tf 2 O in the presence of CuX 2 (X = Br, Cl), Zn powder, and 2,2'-bipyridine affords bromo(chloro)trifluoromethylated products in good yields. CuX 2 plays a dual role as the catalyst and halide source, whereas 2,2'-bipyridine acts as both the activation reagent and ligand.

Dearomatization of indole derivatives offers a straightforward approach to access diverse indolines. To date, the corresponding dearomative transformations involving electron-deficient indoles are limited. Herein, we report a one-electron strategy for dearomatization of electron-deficient indoles via a photoredox-catalyzed hydroalkylation employing commercially available glycine derivatives as the hydrofunctionalization reagents. Followed by DBU-mediated lactamization, structurally appealing lactam-fused indolines are obtained in good to excellent yields with exclusive selectivity.

Cyanation of unactivated primary and secondary alkyl mesylates with Zn(CN) 2 catalyzed by nickel has been developed. The reaction provides an efficient route for the synthesis of alkyl nitriles with wide substrate scope, good functional group tolerance, and compatibility with heterocyclic compounds. Mechanistic studies indicate that alkyl iodide generated in situ serves as the reactive intermediate and the gradual release of alkyl iodide is crucial for the success of the reaction.

A general method for site-selective difluoroalkylation of alkyl carboxylic redox esters with difluoroenoxysilanes through photoredox-catalyzed decarboxylative reaction has been developed. The reaction can also be extended to aliphatic amine derived pyridinium salts. This method has the advantages of high efficiency, mild reaction conditions, and broad substrate scope, including primary, secondary, and sterically hindered tertiaryl alkyl substrates, providing a general and practical route for applications in organic synthesis and pharmaceutical studies.

A gold-catalyzed dearomatization reaction of β-naphthol derivatives via intramolecular hydroalkylation of alkynes is described. In the presence of 5 mol % Au complex, various spironaphthalenones were obtained from α-tethered alkyne β-naphthols in good to excellent yields (76-99%) under open-flask conditions.

The oxidative C-H aryloxydifluoromethylation and arylthiodifluoromethylation of heteroaromatic compounds through the decarboxylation of easily accessible aryloxydifluoroacetic acids and arylthiodifluoroacetic acids, respectively, are disclosed. These reactions are promoted by the combination of catalytic AgNO 3 and Selectfluor or K 2 S 2 O 8 to give ArOCF 2 - and ArSCF 2 -substituted heteroaromatic compounds in moderate to high yields.

A nickel-catalyzed homo- and cross-coupling of allylic alcohols to 1,5-dienes in the presence of B 2 pin 2 with excellent regioselectivity has been developed. Mechanistic studies indicate that the reaction proceeds via sequential nickel-catalyzed borylation of allyl alcohols followed by cross-coupling of the resulting allyl boronates with allyl alcohols. The method was effectively applied to nickel-catalyzed allylation of aldehydes using allylic alcohols directly.

Ni-catalyzed intermolecular allylic dearomatization reaction of β-naphthols with allylic alcohols was achieved. By utilizing Ni(cod) 2 as a catalyst precursor, DPEphos as a ligand and 4 Å molecular sieves as additives, the dearomatization reaction of β-naphthols with aryl allylic alcohols proceeded smoothly under mild conditions, affording the desired β-naphthalenone products bearing a quaternary carbon center in moderate to good yields with excellent linear selectivity.

CuCl/( R , R )-Ph-BPE-catalyzed asymmetric hydroallylation of 1,2-dihydroquinolines, prepared from readily available quinolines, was developed. The optically active tetrahydroquinolines (THQs) bearing an allylic functionality at position 4 were obtained in good yields and excellent enantioselectivity. The introduced allylic groups are amenable to diverse transformations, thus offering chances to rapidly expand the THQ libraries.

ZnBr 2 -catalyzed stereoselective [5 + 2] annulation of N -acryloyl indoles with cyclic sulfonyl enamides is reported, providing a concise and efficient synthesis of isoeburnamonine, which is the key intermediate for norvincamine. Both [2 + 2] and [4 + 2] cycloadducts, depending on the ring size of the enamides, have been shown to be the important intermediates for this [5 + 2] annulation.

A diastereo- and enantioselective propargylic substitution reaction between propargylic carbonates and α-substituted nitroacetates catalyzed by a Cu-pybox complex is described. This method allows the preparation of a series of non-proteinogenic quaternary α-amino acid precursors featuring two contiguous stereogenic centers and a terminal alkyne moiety in high yields with good to excellent diastereo- and enantioselectivities in most cases. The propargylated adducts were elaborated into a diverse set of quaternary α-amino acid derivatives.