Zhi Guan

A visible‐light‐induced redox‐neutral protocol is developed for the synthesis of diverse N ‐aryl γ‐lactams via a decarboxylative radical addition/intramolecular transamidation cascade from α,β‐unsaturated N ‐acylindoles and α‐amino acids. The N ‐acylindole motif serves dual roles as an activated acyl donor and a traceless indole leaving group, driving the key transamidation step thermodynamically. Notably, the released indole can be recovered and reused for substrate synthesis, thus improving the atom economy of the process. The reaction features broad substrate scope and mild conditions. This method provides a practical and green complement to conventional γ‐lactam synthesis.

Thioesters serve as important pharmacophores and synthetic intermediates, yet their conventional synthesis typically requires high temperatures, transition metal catalysts, or toxic and malodorous thiols. Herein, we present a simple and green electrochemical approach for the thioesterification of carboxylic acids with aromatic disulfides as direct sulfur surrogates, promoted by triphenylphosphine. The reaction proceeds under mild conditions without requiring transition metals, external reducing agents, or inert atmosphere. A broad scope of aromatic, aliphatic, and heterocyclic carboxylic acids, along with diversely substituted aromatic disulfides, are well tolerated, affording the corresponding thioesters in moderate to excellent yields. Gram‑scale synthesis and downstream derivatization demonstrate the practical utility of this protocol. Mechanistic studies support a radical-radical cross‑coupling pathway. This work offers a scalable and environmentally benign alternative for thioester synthesis.

An electrochemical strategy enables the direct conversion of inert methyl groups in arenes into valuable nitriles under mild and sustainable conditions.

This work presents a novel photocatalytic halogen atom transfer (XAT) strategy, enabling redox-neutral C(sp³)-C(sp³) coupling between N-aryl tetrahydroisoquinolines and unactivated alkyl halides. The strategy employs an α-aminoalkyl radical, generated in situ from N-aryl tetrahydroisoquinoline via single-electron transfer (SET) oxidation under photocatalytic conditions. This radical acts as a traceless XAT reagent to activate alkyl bromides/chlorides/iodides (C-X bond), forming key alkyl carbon radicals. Simultaneously, the same N-aryl tetrahydroisoquinoline molecule is converted into an iminium intermediate after the XAT event, which functions as an endogenous coupling partner to capture the alkyl radicals, ultimately forming C-C bonds. This transformation proceeds under redox-neutral conditions without external XAT reagents or stoichiometric reductants.

The dihydroquinolin-2-one scaffold is a privileged structure in many bioactive compounds. We describe a visible-light-driven photoredox catalysis strategy for the decarboxylative coupling of 2-quinolinones with α-amino acids, enabling the efficient synthesis of 3-aminoalkyl dihydroquinolin-2-ones. This method utilizes readily available α-amino acids to generate α-aminoalkyl radicals under mild conditions. It exhibits a broad substrate scope, accommodating natural α-amino acids (both cyclic and acyclic), other α-heteroatom-substituted acids, and aliphatic carboxylic acids. This redox-neutral transformation proceeds under simple conditions with good functional group tolerance, eliminates the need for sacrificial reagents or hydrogen atom donors, and exhibits good step economy. Decarboxylation generates CO₂ as the only byproduct.

A visible-light photocatalytic method is reported for the regio- and stereoselective synthesis of polysubstituted γ-lactams from N-arylglycines and Morita-Baylis-Hillman (MBH) acetates. The reaction proceeds through sequential radical aminoalkylation of the dual electrophilic MBH acetate by photogenerated α-aminoalkyl radicals, forming a key γ,γ'-diaminobutyl ester intermediate that undergoes regioselective lactamization. This strategy provides a mild and efficient route to privileged γ-lactam scaffolds, demonstrating the rational integration of two versatile synthons in cascade reactions.

A visible-light-driven radical cascade cyclization strategy has been developed for the synthesis of cyanoalkylated benzoxazine derivatives.

A strategy for the synthesis of δ-keto esters via multicomponent 1,2-alkylacylation of alkenes has been developed using synergistic photoredox and N-heterocyclic carbene (NHC) dual catalysis. This transformation features good step economy.

A novel and environmentally benign electrochemical method has been developed for the regioselective C6 thiocyanation of tetrahydroquinolines using potassiu

A novel electrochemical method for the direct synthesis of 2-thiazolidinone derivatives is reported. Readily available aryl alkenes, KSCN and H₂O are utilized as starting materials to produce 4-aryl-2-thiazolidinones in moderate to satisfactory yields. KSCN acts as a radical precursor and nucleophile, while H₂O participates in the formation of carbamoyl groups, ensuring high atom economy. The reaction proceeds under mild and environmentally friendly conditions, constructing the 2-thiazolidinone heterocycle without the need for metals, catalysts, external oxidants, or sacrificial agents. It exhibits excellent product diversity and functional-group tolerance. The reaction is conducted in an undivided cell under open-air conditions and is operationally simple. Late-stage modification of natural products, and scale-up synthesis further demonstrate the practical application of the method.