Direct Synthesis of Alkylthioimidazoles: One‐Pot Three‐Component Cross‐Coupling Mediated by Paired Electrolysis

A General Radical Functionalization of Quinoxalin-2(1H)-ones via a Donor-Acceptor Inversion Strategy

The radical donor-acceptor inversion strategy represents a highly promising approach in the field of radical chemistry. The present study initially describes a metal-free, versatile, and modular approach for the radical functionalization of quinoxalin-2(1H)-ones via a strategy of radical donor-acceptor inversion under simple reaction conditions. More than 66 examples were provided in moderate yields. The mechanistic study has confirmed that the driving force behind this radical reaction is the in situ formation of a salt through the interaction between quinoxalin-2(1H)-ones and acid/HFIP, which exhibits potent oxidation properties. Additionally, it has been observed that the evident hydrogen bonding between quinoxalin-2(1H)-ones and HFIP can effectively mitigate the oxidation potential.

A General Photoactive H-Bonding EDA Complex Model Drives the Selective Hydrothiolation and Hydroxysulfenylation of Carbonyl Activated Alkenes

Excitation of photoactive electron donor-acceptor (EDA) complexes to generate radical is a promising approach in radical chemistry. In this study, we introduce a new model of H-bonding EDA complexes for the selective hydrothiolation and hydroxysulfenylation of carbonyl-activated alkenes with diverse thiols under visible light conditions. The reliability of this H-bonding EDA complex model has been confirmed by meticulous experimental and theoretical calculations. Mechanistic investigations have revealed the significant influence of the solvent in determining whether the excitation of photoactive H-bonding EDA complex leads to charge transfer (CT) or energy-charge transfer (En-CT), thereby controlling Markovnikov and anti-Markovnikov selectivity. Notably, the Quantum Theory of Atoms in Molecules (QTAIM) analysis clearly shows that the excited state of the C=O-H-S EDA complex involves closed-shell partially covalent interactions.

Synthesis of Sulfur-Containing Trisubstituted Imidazoles by One-Pot, Multicomponent Reaction via Electron Donor-Acceptor Complex Photoactivation

Rapid and efficient construction of multifunctionalized skeletons through a one-pot multicompound domino reaction has been recognized as a simple and practical strategy. Herein, a visible-light-enabled three-component reaction of isothiocyanates, isocyanides, and thianthrenium salt-functionalized arenes is presented, which affords a facile approach to sulfur-containing trisubstituted imidazoles in good yields with a broad substrate scope and excellent functional group tolerance. The byproduct thianthrene is recovered in quantity, thereby ultimately reducing the production of chemical waste. The developed methodology has potential value for the discovery and development of thioimidazole-based drugs.

Paired Electrolysis-Enabled Arylation of Quinoxalin-2(1H)-ones

The first paired electrolysis-enabled arylation of quinoxalin-2(1H)-ones was achieved using cyanoarenes as the arylation reagents. A variety of 3-arylquinoxalin-2(1H)-ones with various important functional groups were obtained in moderate to good yields under metal- and chemical oxidant-free conditions. With a pair of reductive and oxidative processes occurring among the substrates and reaction intermediates, the power consumption can be dramatically reduced.

Base-promoted one-pot three-component desulphurization cross-coupling access to 4-cyanoimidazole

A novel, straightforward, and scalable base-mediated one-pot three-component desulphurization cross-coupling strategy is reported for the synthesis of 4-cyanoimidazole derivatives. Over 35 examples are provided and achieved yields exceeding 85%. Notably, the majority of these readily available compounds can be isolated through simple filtration, thereby circumventing the need for laborious column chromatography. Besides, the present protocol can be scaled up to 10 mmol with a yield of 87%, demonstrating promising potential for industrial applications.

Electro-Triggered Cascade Cyclization to Access Phosphinyl-Substituted N-Containing Heterocycles

An electro-triggered cascade cyclization strategy was disclosed with concomitant phosphinylation and N-heterocycle construction. It provides a novel and environmentally friendly approach to access phosphinyl-substituted N-heterocycles with no external metal catalyst, oxidant, or heating. Mechanistic studies have revealed that anodic oxidation of H-phosphorus compounds occurs first to generate the key P-centered radical directly and cathodic reduction leads to the concurrent release of molecular hydrogen or methane. This protocol features simple operation, broad substrate scope, clean and mild conditions, and atom and step economy to form heterocycle-containing organophosphorus scaffolds.

Electrooxidation-induced selective cleavage of C–N bonds of tertiary amines to access thioureas, selenoureas, and 2-aminated benzoselenazoles

A metal-free, operationally simple, and scalable electrooxidation-induced selective cleavage of C–N bonds of tertiary amines to access thiourea, selenourea, and 2-aminated benzoselenazole derivatives has been developed.

Electrochemical β-chlorosulfoxidation of alkenes

A green and sustainable electrochemical β-chlorosulfoxidation of alkenes with readily available thiols and hydrochloride as the limiting agents has been developed.