Electrochemical Organoselenium-Catalyzed Intermolecular Hydroazolylation of Alkenes with Low Catalyst Loadings.

The organoselenium-catalyzed amination of alkenes is a promising way to construct functionalized amines. However, the use of chemical oxidants and the unavoidable formation of allylic amine or enamine are the two main limitations of these methodologies. Against this background, we herein report an electro-selenocatalytic regime for the hydroazolylation of alkenes with azoles under external oxidant-free conditions with low catalyst loadings. Moreover, this protocol enables the generation of amines without vinyl substituents.

Electrophotocatalytic C-H Functionalization of N-Heteroarenes with Unactivated Alkanes under External Oxidant-Free Conditions.

The Minisci alkylation of N-heteroarenes with unactivated alkanes under external oxidant-free conditions provides an economically attractive route to access alkylated N-heteroarenes but remains underdeveloped. Herein, a new electrophotocatalytic strategy to access alkyl radicals from strong C(sp3 )-H bonds was reported for the following Minisci alkylation reactions in the absence of chemical oxidants. This strategy realized the first example of cerium-catalyzed Minisci alkylation reaction directly from abundant unactivated alkanes with excellent atom economy. It is anticipated that the general design principle would enrich catalytic strategies to explore the functionalizations of strong C(sp3 )-H bonds under external oxidant-free conditions with H2 evolution.

Nickel-catalyzed electrochemical reductive decarboxylative coupling of N-hydroxyphthalimide esters with quinoxalinones.

Herein the first example of electrochemically enabled, NiCl2-catalyzed reductive decarboxylative coupling of N-hydroxyphthalimide (NHP) esters with quinoxalinones is reported. A range of primary, secondary, tertiary aliphatic carboxylic acids and amino acid-derived esters were tolerated well. This decarboxylative coupling allows access to structurally diverse 3-alkylated quinoxalinones in up to 91% yields.

An Ir-photoredox-catalyzed decarboxylative Michael addition of glyoxylic acid acetal as a formyl equivalent.

We reported herein an iridium-photoredox-catalyzed decarboxylative conjugated addition of glyoxylic acid acetals with various Michael acceptors, including unsaturated amide, ester, aldehyde, ketone, and nitrile under irradiation. Vinyl pyridine and α-aryl styrene are also suitable substrates. The reaction offers various types of acetal products, which are of synthetic significance as protected aldehydes.

Photoredox catalysis enabled alkylation of alkenyl carboxylic acids with N-(acyloxy)phthalimide via dual decarboxylation.

A ruthenium based photoredox catalyst in combination with a substoichiometric amount of 1,4-diazabicyclo[2.2.2]octane (DABCO) efficiently catalyzed dual decarboxylative couplings between alkenyl carboxylic acids and N-(acyloxy)phthalimides derived from aliphatic carboxylic acids, delivering alkylated styrene derivatives in a high regio- and stereo-selective manner under mild reaction conditions. Various types of secondary, tertiary, and quaternary aliphatic carboxylic acids as well as α-amino acids can be used as suitable substrates. Mechanistic analysis suggested that the reaction proceeds through a radical mechanism mediated by a Ru(i)/Ru(ii) catalytic cycle with DABCO acting both as the base and the co-catalyst for single electron transfer.