“…Among them, the synthesis of important C5-halogenated products gained particular attention since Stahl et al reported the first chlorination example using LiCl as the halogen source [10]. Following this pioneering work, elegant strategies for the C5-H bromination of the quinoline ring employing simple inorganic and organic bromine-containing compounds such as Br 2 , CuBr, CuBr 2 , LiBr, NaBr, KBr, HBr, NH 4 Br, and tetrabutylammonium bromide (TBAB) as halogen sources have been realized (Scheme 1, reaction 1) [11][12][13][14][15][16][17][18][19][20]. Another category of extensively used bromination reagents are brominated imides, such as N-bromosuccinimide (NBS), N-bromosaccharin (NBSA), tribromoisocyanuric acid (TBCA), 1,3-dibromo-5,5-dimethylhydantoin (DBDMH), and so on (Scheme 1, reaction 2) [21][22][23][24].…”