Recent Advances in Transition-Metal-Catalyzed, Directed Aryl C–H/N–H Cross-Coupling Reactions

Abstract

Amination and amidation of aryl compounds using a transition-metal-catalyzed cross-coupling reaction typically involves prefunctionalization or preoxidation of either partner. In recent years, a new class of transition-metal-catalyzed cross-dehydrogenative coupling reaction has been developed for the direct formation of aryl C–N bonds. This short review highlights the substantial progress made for ortho-C–N bond formation via transition-metal-catalyzed chelation-directed aryl C–H activation and gives an overview of the challenges that remain for directed meta- and para-selective reactions.1 Introduction2 Intramolecular C–N Cross-Dehydrogenative Coupling2.1 Nitrogen Functionality as Both Coupling Partner and Directing Group2.2 Chelating-Group-Directed Intramolecular C–N Bond Formation3 Intermolecular C–N Cross-Dehydrogenative Coupling3.1 ortho-C–N Bond Formation3.1.1 Copper-Catalyzed Reactions3.1.2 Other Transition-Metal-Catalyzed Reactions3.2 meta- and para-C–N Bond Formation4 C–N Cross-Dehydrogenative Coupling of Acidic C–H Bonds5 Conclusions

Recent Advances in the Application of Selectfluor as a “Fluorine‐free” Functional Reagent in Organic Synthesis

“…Transition metal catalysed/mediated cross-coupling is a powerful tool for the construction of valuable organic compounds. [5][6] Within this reaction category, the Au/Selectfluor system has been widely used in "fluorine-free" functionalizations. [4,[7][8] The pioneer work in this field was reported by the Zhang group in 2009.…”

Synthesis of heterocycles via aerobic oxidation

“…This transformation typically requires the use of transition metal catalysts, and many reports using Pd and other noble metals, as well as a variety of oxidants, were reported. 72 More recently, the use of Cu and other base metals have instead become predominant, and some procedures under metal-free conditions have also been successfully applied. Due to the many examples reported in the recent literature, only a selection will be reported in this section.…”

Iodine-Mediated Intramolecular C–H Amination of Benzimidazoles: A Metal-Free Route to Dihydroimidazobenzimidazoles

“…FT-IR (KBr): 2923, 2853, 1625, 1539, 1451, 1417, 1375, 1188, 1172, 1091 cm -1 . 1 H NMR (600 MHz, CDCl 3 ): δ = 8.00 (d, J = 8.4 Hz, 2 H), 7.69 (d, J = 1.8 Hz, 1 H), 7.37 (t, J = 7.8 Hz, 1 H), 7.36-7.30 (m, 4 H), 6.97-6.95 (m, 3 H), 6.58 (d, J = 8.4 Hz, 1 H), 5.43-5.41 (m,1 H),1 H),4.15 (dd,J = 10.2,6.6 Hz,1 H),2.44 (s,3 H). 0, 148.7, 145.6, 136.2, 133.4, 130.2, 129.6, 129.5, 128.2, 128.1, 126.3, 122.2, 119.8, 109.8, 60.6, 57.0, 21.8.…”