Photoassisted Cross-Coupling Reaction of α-Chlorocarbonyl Compounds with Arylboronic Acids

Photoinduced Pd-Catalyzed Intramolecular 6-endo Heck Reaction of Alkyl Halides

A novel photocatalytic palladium-induced 6-endo-selective alkyl Heck reaction of unactivated alkyl iodides and alkyl bromides has been described. This strategy facilitates the gentle and efficient synthesis of a variety of 5-phenyl-1,2,3,6-tetrahydropyridine derivatives. It demonstrates a broad substrate tolerance and excellent 6-endo selectivity. Unlike the high-temperature requirements of traditional alkyl Heck reactions, this transformation efficiently proceeds at room temperature and shows significant promise for industrial-scale applications. Mechanistic investigations reveal that this alkyl Heck reaction proceeds via a hybrid palladium-radical process.

Recent Advances in Visible Light Induced Palladium Catalysis

Visible light-induced Pd catalysis has emerged as a promising subfield of photocatalysis. The hybrid nature of Pd radical species has enabled a wide array of radical-based transformations otherwise challenging or unknown via conventional Pd chemistry. In parallel to the ongoing pursuit of alternative, readily available radical precursors, notable discoveries have demonstrated that photoexcitation can alter not only oxidative addition but also other elementary steps. This Minireview highlights the recent progress in this area.

Design and synthesis of novel PPO-inhibiting pyrimidinedione derivatives safed towards cotton

Developing innovative and effective herbicides is of utmost importance since weed management has become a worldwide agricultural production concern, resulting in severe economic losses every year. In this study, a series of new pyrimidinedione compounds were developed via combination of pyrimidinediones with N-phenylacetamide moiety. The herbicidal activity test (37.5-150 g of ai/ha) indicated that most of the new derivatives exhibited excellent herbicidal activity against dicotyledonous weeds, but less against grasses. Among them, compound 34 was identified as the best postemergence herbicidal activities against six species of weeds (Amaranthus retrof lexus, AR; Abutilon theophrasti, AT; Veronica polita, VP; Echinochloa crusgalli, EC; Digitaria sanguinalis, DS; Setaria viridis, SV), which were comparable to the commercial control agent saflufenacil (≥90%). The protoporphyrinogen oxidase (PPO; EC. 1.3.3.4) activity experiment suggested that compound 34 could significantly reduce the PPO content in weeds, the relative expression levels of the PPO gene were verified by real-time quantitative polymerase chain reaction (RT-qPCR), and the results were consistent with the trend of the enzyme activity data. Molecular docking showed that compound 34 could occupy the PPO enzyme catalytic substrate pocket, which played an excellent inhibitory effect on the activity of receptor protein. Meanwhile, the tolerance of compound 34 to cotton was better than that of the commercial agent saflufenacil at 150 g of ai/ha. Thus, compound 34 exhibits the potential to be a new PPO herbicide for weed control in cotton fields. This study provided a basis for the subsequent structural modification and mechanism research of pyrimidinedione derivatives.

Carbonyl-Assisted Iridium-Catalyzed C-H Amination Using 2,2,2-Trichloroethoxycarbonyl Azide

The carbonyl-directed, mono C-H amination of arenes has been achieved using [Cp*Ir(III)Cl₂]₂ as the catalyst and 2,2,2-trichloroethoxycarbonyl (Troc) azide as an aminating reagent. The amination proceeds smoothly with a variety of arylcarbonyl compounds, including alkyl and vinyl arylketones, secondary and tertiary aryl amides, and acetyl indoles. The resulting ortho-TrocNH arylcarbonyl compounds are easily transformed to the corresponding free arylamines, aryl carbamates, or aryl ureas. Taking advantage of the electrophilic nature of both Troc and carbonyl groups in ortho-TrocNH arylcarbonyl compounds, the subsequent cyclization with dinucleophilic reagents has also been demonstrated. This provides an efficient strategy for the construction of aryl-fused N-heterocycles.