Asymmetric Michael Addition of Ketones to Alkylidene Malonates and Allylidene Malonates via Enamine–Metal Lewis Acid Bifunctional Catalysis

Novel enamine–metal Lewis acid bifunctional catalysts were successfully applied to the asymmetric Michael addition of ketones to alkylidene malonates, offering excellent stereoselectivity (up to >99% <i>ee</i> and >99:1 <i>dr</i>). The asymmetric Michael addition of ketones to allylidene malonates was also achieved

Asymmetric Michael Addition of Ketones to Alkylidene Malonates and Allylidene Malonates via Enamine–Metal Lewis Acid Bifunctional Catalysis

Novel enamine–metal Lewis acid bifunctional catalysts were successfully applied to the asymmetric Michael addition of ketones to alkylidene malonates, offering excellent stereoselectivity (up to >99% <i>ee</i> and >99:1 <i>dr</i>). The asymmetric Michael addition of ketones to allylidene malonates was also achieved

Cu-Catalyzed Three-Component Coupling of Aryne, Alkyne, and Benzenesulfonothioate: Modular Synthesis of <i>o</i>‑Alkynyl Arylsulfides

A copper-catalyzed three-component coupling reaction of in situ formed arynes, terminal alkynes, and benzenesulfonothioates is described. This reaction provides an efficient modular synthesis of <i>o</i>-alkynyl arylsulfides from easily available starting materials. This process involves one C–S bond and one C–C bond formation in one pot

Atom Transfer Radical Addition to Alkynes and Enynes: A Versatile Gold/Photoredox Approach to Thio-Functionalized Vinylsulfones

An efficient intermolecular atom-transfer addition reaction of alkynes via the combination of visible-light photoredox catalysis and gold catalysis has been developed, affording diverse trifluoromethylthio- and difluoromethylthio-functionalized vinylsulfones with high stereoselectivity in good yields. Thiosulfonylation reaction of enyne can also be realized for constructing functionalized carbo- and heterocycles through a radical cascade cyclization process. These reactions proceed through a gold-assisted sulfonyl radical addition pathway

Copper-Catalyzed Oxidative Trifunctionalization of Olefins: An Access to Functionalized β‑Keto Thiosulfones

Aerobic oxidative trifunctionalization of olefins for the synthesis of functionalized β-keto thiosulfones has been described. The transformation proceeds through molecular oxygen activation under copper catalysis and forms the two new C–S bonds in a single operation using mild conditions. A novel Cu-catalyzed sulfonyl radical addition/oxidation/funtionalization relay mechanism was proposed for the discovered reaction

Atom Transfer Radical Addition to Alkynes and Enynes: A Versatile Gold/Photoredox Approach to Thio-Functionalized Vinylsulfones

An efficient intermolecular atom-transfer addition reaction of alkynes via the combination of visible-light photoredox catalysis and gold catalysis has been developed, affording diverse trifluoromethylthio- and difluoromethylthio-functionalized vinylsulfones with high stereoselectivity in good yields. Thiosulfonylation reaction of enyne can also be realized for constructing functionalized carbo- and heterocycles through a radical cascade cyclization process. These reactions proceed through a gold-assisted sulfonyl radical addition pathway

In Situ Construction of Three Anion-Dependent Cu(I) Coordination Networks as Promising Heterogeneous Catalysts for Azide–Alkyne “Click” Reactions

Three Cu­(I) coordination networks, namely, {[Cu₂(bpz)₂­(CN)­X]·CH₃CN}_<i>n</i>, (X = Cl, <b>1</b>; I, <b>3</b>), {[Cu₆(bpz)₆­(CH₃CN)₃­(CN)₃Br]·2OH·14CH₃CN}_<i>n</i>, (<b>2</b>, bpz = 3,3′,5,5′-tetramethyl-4,4′-bipyrazole), were prepared by using solvothermal method. The cyanide ligands in these networks were generated in situ by cleavage of C–C bond of MeCN under solvothermal condition. The structures of these networks are dependent on halogen anions. Complex <b>1</b> is a ladderlike structure with μ₂-CN^– as rung and μ₂-bpz as armrest. The Cl^– in <b>1</b> is at terminal position but does not extend the one-dimensional (1D) ladder to higher dimensionalities. Complex <b>2</b> is a three-dimensional (3D) framework comprised of novel planar [Cu₃Br] triangle and single Cu nodes, which are extended by μ₂-bpz and μ₂-CN^– to form a novel (3,9)-connected <b>gfy</b> network. Density functional theory calculations showed that single-electron delocalization of Br atom induces the plane structure of [Cu₃Br]. Complex <b>3</b> also possesses a similar ladderlike subunit as in <b>1</b>, but the I^– acts as bidentate bridge to extend the ladder to 3D framework with a four-connected <b>sra</b> topology. The three networks show notable catalytic activity on the click reaction. The compared catalytic results demonstrate that complex <b>2</b> possesses the best catalysis performance among three complexes, which is ascribed to the largest solvent-accessible void (porosity: <b>2</b> (29.4%) > <b>1</b> (25.7%) > <b>3</b> (17.6%)) and the more Cu­(I) active sites in <b>2</b>. The present combined structure–property studies provide not only a new synthetic route to obtain a new kind of catalyst for click reaction but also the new insights on catalyst structure–function relationships

Copper(I)-Catalyzed Three-Component Click/Persulfuration Cascade: Regioselective Synthesis of Triazole Disulfides

A copper­(I)-catalyzed three-component CuAAC/persulfuration reaction providing rapid access to asymmetric triazole disulfides has been developed. The interrupted click reaction shows broad substrate scope, complete regioselectivity, and excellent functional group tolerability

Bench-Stable 5‑Stannyl Triazoles by a Copper(I)-Catalyzed Interrupted Click Reaction: Bridge to Trifluoro­methyl­triazoles and Trifluoro­methyl­thiotriazoles

Metalated triazoles are the key reactive intermediate of the current click reaction (CuAAC). Bench-stable 5-stannyl triazoles are obtained by a copper-catalyzed interrupted click reaction of easily available terminal alkynes. Subsequent palladium-catalyzed cross-coupling reactions, electrophilic trifluoro­methylthiolation and trifluoromethylation, generate diverse 1,4,5-trisubstituted triazoles efficiently, which the traditional click reaction is unable to do

Copper(I)-Catalyzed Three-Component Click/Alkynylation: One-Pot Synthesis of 5‑Alkynyl-1,2,3-triazoles

A copper­(I)-catalyzed tandem CuAAC/alkynylation reaction of various alkynes, organic azides, and bromoalkynes to provide rapid access to 5-alkynyl-1,2,3-triazoles has been developed. The reaction proceeded via a copper-catalyzed alkyne azide cycloaddition followed by interception of the in situ formed cuprate–triazole intermediate with bromoalkyne. This reaction offers a new method to afford fully substituted triazoles in high yields with complete regioselectivity under mild reaction conditions