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In this protocol, we demonstrate our discovery that iron is able to efficiently catalyze the reductive allylic defluorinative ketyl olefin coupling reaction between α-trifluoromethyl alkenes and unactivated ketones. This operationally simple cross-electrophile reaction circumvents the use of pre-generated organometallics and allows for the synthesis of diverse functional-group-rich tertiary

Herein we report a nickel/photo-cocatalyzed C(sp2)-H allylation of aldehydes and formamides wherein both allyl acetates and allyl alcohols can be used as the allylating agents. In this reaction, radical-type umpolung of the formyl moiety is enabled by tetrabutylammonium decatungstate as a hydrogen-atom-transfer photocatalyst, whereas nickel serves to cleave the C-O bond of allyl acetates or allyl alcohols. The synergistic effect of these two catalysts provides new access to various β,γ-unsaturated ketones and amides with high selectivities.

Aldehydes and aziridines are both intrinsic electrophilic reagents, and thus the coupling reaction between these two compounds is highly challenging. In this protocol, the merger of nickel and hydrogen-atom-transfer photocatalysis successfully enables the ring opening of N-tosyl styrenyl aziridines with aldehydes, providing a novel and atom-economical access to a variety of β-amino ketones with complete regiocontrol. The preliminary mechanistic studies reveal that the ring opening reaction proceeds with a cooperative catalytic mode: aldehydes are converted into acyl radicals by tetrabutylammonium decatungstate under irradiation, whereas the nickel catalyst is engaged in the ring opening of aziridines and the following carbon-carbon bond-forming step.

Herein we report a nickel-catalyzed asymmetric reductive dicarbamoylation of alkenes, in which tethered carbamoyl chlorides and isocyanates serve as distinct electrophilic carbamoylating agents, providing new access to chiral oxindoles bearing an amide-substituted quaternary stereogenic center.

Herein we report a nickel-catalyzed cross-electrophile ring-opening reaction of vinyl epoxides wherein aryl iodides, alkyl iodides, and benzyl chlorides can all serve as the electrophilic coupling partners, providing a new approach to preparing multisubstituted allylic alcohols. This new method features broad substrate scope (76 examples), good step-economy, and high L/B- and

Herein, we demonstrate the successful use of robust phenolic esters as an electrophilic acyl source in the reaction with diverse primary and secondary unactivated alkyl bromides. The cleavage of the relatively inert C-O bond is facilitated by the neighboring coordinating hydroxyl or sulfonamide moiety. By circumventing the use of pregenerated organometallics, this method allows efficient preparation of a variety of o-hydroxyl and tosyl-protected o-amino aryl ketones with high compatibility with a wide range of functionalities.

Herein we successfully applied Katritzky salts as the alkyl electrophile in the reductive allylic defluorinative cross-coupling reaction with α-trifluoromethyl alkenes. The merger of C–F and C–N bo...

A simple, direct, and highly enantioselective synthesis of spiro-oxindole piperidin-2-one derivatives was achieved through an aza-Michael/Michael cyclization cascade sequence using a squaramide catalyst. The desired products were obtained in excellent yields (up to 99%) and good to high stereoselectivities (up to20:1 dr and up to 99% ee) under mild conditions.

Herein, we report a method for efficient synthesis of gem-difluorobishomoallylic alcohols starting from trifluoromethyl-substituted alkenes and epoxides via a titanocene-catalyzed reductive domino reaction, which consists of a Ti(III)-mediated radical-type ring opening and the following allylic defluorinative cross-coupling reaction via sequential radical addition and β-F elimination. Notably, complete regioselectivity and high tolerance of functionalities can be achieved in this reaction. Furthermore, diverse 6-fluoro-3,4-dihydro-2H-pyrans have been prepared through derivatization of the cross-coupling products in one single step.

Herein, we report a nickel-catalyzed asymmetric two-component reductive dicarbofunctionalization of aryl iodide-tethered unactivated alkenes using benzyl chlorides as the challenging coupling partner. This arylbenzylation reaction enables the efficient synthesis of diverse benzene-fused cyclic compounds bearing a quaternary stereocenter with a high tolerance of sensitive functionalities in highly enantioselective manner. The preliminary mechanistic investigations suggest a radical chain reaction mechanism.

Herein we report a nickel/photo-cocatalyzed C(sp

Aldehydes and aziridines are both intrinsic electrophilic reagents, and thus the coupling reaction between these two compounds is highly challenging. In this protocol, the merger of nickel and hydrogen-atom-transfer photocatalysis successfully enables the ring opening of

By merging C-F and C-C bond activation in the cross-electrophile coupling, we developed an efficient cyanide-free synthesis of diverse functional-group-rich cyano-substituted gem-difluoroalkenes using cyclobutanone oxime esters and trifluoromethyl alkenes as precursors. Notably, this Ni-catalyzed reaction is bestowed with broad substrate scope, low catalyst loading, complete regioselectivities, and high tolerance of a wide range of sensitive functional groups. Preliminary mechanistic studies indicate that an iminyl radical-initiated C-C bond cleavage is involved in the reaction pathway.

Herein, we present a nickel-catalyzed three-component reductive alkylacylation of electron-deficient activated alkenes with tertiary alkyl bromides and acid anhydrides. This method enables the efficient preparation of a variety of ketones with broad substrate scope and high functionality tolerance starting from simple precursors. On the basis of the preliminary mechanistic investigations, a catalytic cycle involving the synergistic interaction of nickel, zinc, and MgCl2 is proposed as the major reaction pathway.

Herein we successfully applied Katritzky salts as the alkyl electrophile in the reductive allylic defluorinative cross-coupling reaction with α-trifluoromethyl alkenes. The merger of C-F and C-N bond cleavage via the synergistic effect of nickel and zinc allows the efficient synthesis of diverse

In this protocol aryl halides and α-bromo acetates are efficiently cross-coupled with an array of (hetero)aromatic and aliphatic aldehydes under the cooperative catalysis of nickel and tetrabutylammonium decatungstate as a hydrogen-atom-transfer photocatalyst. This method provides a concise approach to a variety of ketones with high compatibility of various functional groups.

Unactivated alkyl chlorides are abundant building blocks in organic synthesis, but they have been rarely engaged in cross-electrophile coupling. Herein, we report a Ni/Ti-cocatalyzed reductive allylic defluorinative cross-coupling between trifluoromethyl alkenes and unactivated alkyl chlorides and bromides, enabling the efficient preparation of diverse functional-group-rich gem-difluoroalkenes. Notably, synthesis of the gem-difluoroalkene analogues of azaperone, haloperidol, and benperidol was also accomplished using our method as a key step.

Reported is a nickel-catalyzed reductive arylalkylation of unactivated alkenes tethered to aryl iodides with redox active N-hydroxyphthalimide esters as the alkyl source through successful merging of migratory insertion and decarboxylative cross-coupling in a cascade. This new method avoids the use of pregenerated organometallic reagents and thus enables the synthesis of diverse benzene-fused carbo- and heterocyclic compounds with high tolerance of a wide range of functional groups.

An asymmetric Ni-catalyzed intramolecular reductive Heck reaction of unactivated alkenes tethered to aryl bromides has been accomplished, providing a variety of benzene-fused cyclic compounds bearing a quaternary stereogenic center in good to excellent yields and high enantioselectivities. A mechanism has been proposed, which involves the enantiodetermining migratory insertion and the following protonation with water or alcoholic solvents as the proton source.

The highly enantioselective preparation of spirooxindoles bearing α,α-disubstituted α-amino-β-keto esters was achieved through [4 + 1] annulation of oxindoles and α-imine-β-oxo-γ,δ-unsaturated esters under mild conditions in good yields (up to 82%) and stereoselectivities (up to >20:1 dr, 96% ee). The reaction is amenable to gram scale synthesis using catalyst loading as low as 1 mol %. The corresponding chiral α,α-disubstituted α-amino-β-keto esters could be easily transformed into cyclopenta[b]indole derivatives without erosion of enantiopurity.

The first catalytic regioselective and stereospecific halogenation of 2,3-epoxy alcohols and 2,3-epoxy sulfonamides has been developed. Under the catalysis of commercially available W- or Mo-salts, complemented by the method using cerium halides, the C-3 selective ring opening of structurally diverse epoxides with Cl-, Br-, and I-nucleophiles afforded various halohydrins in good yields and high regioselectivities.

The Cu-catalyzed asymmetric conjugate hydroboration reaction of β-substituted α-dehydroamino acid derivatives has been established, affording enantioenriched syn- and anti-β-boronate-α-amino acid derivatives with excellent combined yields (83–99%, dr ≈ 1:1) and excellent enantioselectivities (92–98% ee). The hydroboration products were expediently converted into valuable β-hydroxy-α-amino acid derivatives, which were widely used in the preparation of chiral drugs and bioactive molecules.

A palladium-catalyzed aryl C-H bonds activation/acetoxylation reaction utilizing a bidentate system has been explored. This transformation has been applied to a wide array of pyridine and 8-aminoquinoline derivatives and it exhibits excellent functional group tolerance.