Photocatalytic redox-neutral selective single C(sp3)-F bond activation of perfluoroalkyl iminosulfides with alkenes and water

Photoexcited Hantzsch Ester Anions Enabled C-F Bond Activation and Hydro-Difluoroalkylation of Arylethylenes Through Dual-SET Process

In this study, we reported a new approach to activate the C-F bond of trifluoromethylarenes to achieve the hydro-difluoroalkylation of arylethylenes using photoexcited Hantzsch esters (HEs) anions. A wide range of α,α-difluoroalkanes was synthesized. Late-stage functionalization of drug molecules and synthesis of bioactive molecule bioisostere were also presented. Mechanistic studies revealed that the dual-single electron transfer (SET) process of HEs anion was the key to this reaction.

Defluorinative Cyclization of Enamides with Fluoroalkyl Halides Through Two Vicinal C(sp3)─F Bonds Functionalization

Introducing distinctive functional groups to expand the structural diversity and improve the intrinsic properties of parent molecules has been an essential pursuit in organic chemistry. By using perfluoroalkyl halide (PFAH) as a nontraditional, readily available, ideal 1,2-difluoroalkenyl coupling partner, a defluorinative cyclization reaction of enamides for the construction of fluoroalkenyl oxazoles is first developed. The selective and controllable two-fold cleavage of vicinal C(sp3)─F bonds in PFAH not only enables the introduction of a specific 1,2-difluoroalkenyl moiety with ease but also results in the functionalization of two C(sp2)─H bonds of enamides without the need for metal catalyst, photocatalyst, oxidant, or light. The method can be applied to the late-stage modification of complex molecules, synthesis of biological-relevant oxazole analoges, and scale-up synthesis, which all further highlight the real-world utility of this protocol. Mechanistic studies reveal that the reaction possibly proceeds through a radical perfluoroalkylation, consecutive C─F bond heterolytic cleavage, and cyclization process. In addition, the in situ formed perfluoroalkyl radical which may also serve as an essential hydrogen abstractor.

Trifluoromethylated lactams: promising small molecules in the search for effective drugs

Lactams are a crucial class of compounds with broad therapeutic applications, including in the treatment of cancer, diabetes, and infectious diseases. Functionalised lactams are essential core structures in numerous alkaloids and pharmaceuticals. The introduction of fluorine-containing groups, such as a trifluoromethyl (CF3) group, into organic molecules significantly alters their physical and chemical properties. This review highlights the primary biological targets, as well as the most important synthetic pathways, associated with trifluoromethylated β-lactams (four-atom rings), γ-lactams (five-atom rings), δ-lactams (six-atom rings), and ε-lactams (seven atom rings). Furthermore, we analyze the most common lactam scaffolds, evaluating their potential for future chemical synthesis and emphasizing those that merit attention despite having limited reported analogues. This article aims to provide a comprehensive overview of the importance of trifluoromethylated lactams in drug discovery and design.

Radical Reactions in Organic Synthesis: Exploring in-, on-, and with-Water Methods

Radical reactions in water or aqueous media are important for organic synthesis, realizing high-yielding processes under non-toxic and environmentally friendly conditions. This overview includes (i) a general introduction to organic chemistry in water and aqueous media, (ii) synthetic approaches in, on, and with water as well as in heterogeneous phases, (iii) reactions of carbon-centered radicals with water (or deuterium oxide) activated through coordination with various Lewis acids, (iv) photocatalysis in water and aqueous media, and (v) synthetic applications bioinspired by naturally occurring processes. A wide range of chemical processes and synthetic strategies under different experimental conditions have been reviewed that lead to important functional group translocation and transformation reactions, leading to the preparation of complex molecules. These results reveal how water as a solvent/medium/reagent in radical chemistry has matured over the last two decades, with further discoveries anticipated in the near future.