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The gold π-acid activation under electrochemical conditions is achieved. While EAO allows easy access to gold(III) intermediates over alternative chemical oxidation under mild conditions, the reported examples so far are limited to coupling reactions due to the rapid Au^IIIreductive elimination. Using aryl hydrazine-HOTf salt as precursors, the π-activation reaction mode was realized through oxidation relay. Both alkene and alkyne di-functionalization were achieved with excellent functional group compatibility and regioselectivity, which extended the versatility and utility of electrochemical gold redox chemistry for future applications.

 

The styryl dehydro-Diels–Alder reaction with a conjugated diyne is reported. While typical alkyne–styrene condensation requires elevated temperatures (>160 °C), the application of a conjugated diyne allowed for effective transformation under milder conditions (80 °C). The thermally stable triazole–gold (TA–Au) catalyst further improved the reaction yields (up to 95%), producing the desired alkynyl–naphthalene in a single step with molecular oxygen as the oxidant. Sequential alkyne activation resulted in various polyaromatic hydrocarbons (PAHs) in excellent yields, highlighting the efficiency of this new strategy for the preparation of PAHs with good functional group tolerance and structural diversity. 

Enantioselective, intermolecular alkene arylamination was achieved through gold redox catalysis. Screening of ligands revealed chiral P,N ligands as the optimal choice, giving alkene aminoarylation with good yields (up to 80 %) and excellent stereoselectivity (up to 99 : 1er). As the first example of enantioselective gold redox catalysis, this work confirmed the feasibility of applying a chiral ligand at the gold(I) stage, with the stereodetermining step (SDS) at the gold(III) intermediate, thus opening up a new way to conduct gold redox catalysis with stereochemistry control.

 

The gold‐catalyzed intermolecular oxyarylation of alkenes is reported. This work employed the oxidative addition of aryl iodides to Me−DalphosAu⁺for the formation of a Au^III−Ar intermediate. The better binding ability of alkenes over O nucleophiles ensured the success of intermolecular oxyarylation, giving desired products with a broad substrate scope and high efficiency (>50 examples with up to 95 % yield). One‐pot converting of methoxy groups into other nucleophiles allowed achieving alkene difunctionalization with the construction of C−N, C−S, and C−C bonds under mild conditions.

 

The gold‐catalyzed intermolecular oxyarylation of alkenes is reported. This work employed the oxidative addition of aryl iodides to Me−DalphosAu⁺for the formation of a Au^III−Ar intermediate. The better binding ability of alkenes over O nucleophiles ensured the success of intermolecular oxyarylation, giving desired products with a broad substrate scope and high efficiency (>50 examples with up to 95 % yield). One‐pot converting of methoxy groups into other nucleophiles allowed achieving alkene difunctionalization with the construction of C−N, C−S, and C−C bonds under mild conditions.

 

Due to the high oxidation potential between Au^Iand Au^III, gold redox catalysis requires at least stoichiometric amounts of a strong oxidant. We herein report the first example of an electrochemical approach in promoting gold‐catalyzed oxidative coupling of terminal alkynes. Oxidation of Au^Ito Au^IIIwas successfully achieved through anode oxidation, which enabled facile access to either symmetrical or unsymmetrical conjugated diynes through homo‐coupling or cross‐coupling. This report extends the reaction scope of this transformation to substrates that are not compatible with strong chemical oxidants and potentiates the versatility of gold redox chemistry through the utilization of electrochemical oxidative conditions.

 

Due to the high oxidation potential between Au^Iand Au^III, gold redox catalysis requires at least stoichiometric amounts of a strong oxidant. We herein report the first example of an electrochemical approach in promoting gold‐catalyzed oxidative coupling of terminal alkynes. Oxidation of Au^Ito Au^IIIwas successfully achieved through anode oxidation, which enabled facile access to either symmetrical or unsymmetrical conjugated diynes through homo‐coupling or cross‐coupling. This report extends the reaction scope of this transformation to substrates that are not compatible with strong chemical oxidants and potentiates the versatility of gold redox chemistry through the utilization of electrochemical oxidative conditions.