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The modular cyanoalkylamination of alkenes using bench-stable and easy-to-handle α-imino-oxy acid oxime esters as difunctional reagents creates new synthetic avenues. A metal-free photosensitization protocol for the installation of both amino and cyanoalkyl functionalities onto alkene feedstocks in a single step via two differently reactive nitrogen-centered radicals was developed via energy-transfer catalysis. Excellent functional group tolerance and mild reaction conditions also render this protocol suitable for the cyanoalkylamination of pharmaceutically relevant molecule-derived alkenes.

The first photoredox-catalyzed defluoroborylation of polyfluoroarenes with NHC-BH3 has been facilely achieved at room temperature via a single-electron-transfer (SET)/radical addition pathway. This new strategy makes full use of the advantage of photoredox catalysis to generate the key boryl radical via direct activation of a B-H bond. Good functional group tolerance and high regioselectivity offer this protocol incomparable advantages in preparing a wide array of valuable polyfluoroarylboron compounds. Moreover, both computational and experimental studies were performed to illustrate the reaction mechanism.

A novel palladium-catalysed ring-opening [3 + 2]-annulation of spirovinylcyclopropyl oxindole with α,β-unsaturated nitroalkenes is reported. A series of spirooxindole derivatives were synthesized in high yields and good to excellent diastereoselectivities. This developed protocol offers a new and efficient pathway for the assembly of spirooxindoles.

An l-pyroglutamic acid-derived bifunctional organocatalyst was designed and applied in an organocatalytic asymmetric direct aldol reaction between isatins and cyclohexanone, in which an erosion of enantiomeric excess of aldol adduct was unexpectedly observed. Through closely monitoring the reaction and performing extensive control experiments, it was determined that the erosion of ee was attributed to a rare stereospecific retro-aldol process. Moreover, effective manipulation of the retro-aldol process by tuning the use of starting materials was ultimately accomplished, leading to evidently upgraded enantioselectivity and functional group tolerance. This study demonstrates the impact of the hidden reaction pathway on the enantioselectivity in asymmetric transformation.

Practical and diastereospecific three-component 1,3-dipolar cycloaddition reactions of methyleneindolinones, isatins and diverse primary amino acids have been well established. A range of pyrrolidinyldispirooxindole scaffolds with wide structural diversity and complexity were obtained facilely in excellent yields under mild conditions, which hold promising applications in their further pharmacological studies.

A facile and diversified synthesis of functionalized CF2-containing benzoxepine derivatives via photoredox catalysis was achieved in this work. This novel protocol features broad substrate scope, mild reaction conditions, operational simplicity, easy scale-up, and versatile derivatization, which would facilitate its practical and broad applications in the construction of valuable and synthetically challenging heterocycles.

A facile visible-light photocatalytic conjugate addition to prepare 1,4-dicarbonyl compounds has been developed by employing readily available aroyl chlorides as aryl radical sources. This operationally simple method shows a broad scope with regard to both aroyl chlorides and Michael acceptors. As a result, a variety of 1,4-diketones were efficiently synthesized in moderate to good yields.

A photoinduced, phosphoranyl radical-mediated protocol for the direct N-O cleavage of strained cycloketone oximes via a polar/SET crossover process was developed for the first time. This visible-light-driven direct N-O activation mode for oxime offers beneficial features such as streamlined synthetic process and versatile photochemical reactivities. Consequently, the alkenes and α-trifluoromethyl alkenes with varied electronic and structural features acted as competent radical receptors in this protocol, enabling facile accesses to a range of elongated cyano and/or gem-difluoroalkene-bearing compounds.

An efficient intramolecular [3 + 2]-cycloaddition of in situ-formed salicylaldehyde-based N,N′-cyclic azomethine imines was successfully developed to access novel tetracyclic skeleton bearing three contiguous stereogenic centres. This established protocol features high functional-group tolerance, excellent chemical yields, good diastereoselectivities, and variable reaction conditions.

A practical and straightforward synthetic route to construct a variety of 3-CF2/CF3-containing chromones via photoredox catalysis was developed. This novel protocol features a visible-light-induced radical-triggered tandem cyclization.

A diversity-driven three-component 1,3-dipolar cycloaddition of isatins, amino acids and isatin-derived ketimines was developed to facilely assemble dispirooxindole-imidazolidine skeletons bearing vicinal quaternary carbon centers. This protocol features additive-free, minimal solvent usage (0.1 mL DMSO/0.2 mmol scale), wide substrate scope (34 examples), mild reaction conditions (room temperature) and high chemical yield (up to 99%).