Selective Bromination of Pyrrole Derivatives, Carbazole and Aromatic Amines with DMSO/HBr under Mild Conditions

Abstract

Bromination of pyrrole derivatives, carbazole and aromatic amines using the DMSO/HBr system affords high yields of the corresponding bromo compounds. Temperature control used in the bromination of anilines helped to promote selective formation of mono-or di-brominated products. Simple operation, low toxicity and high selectivity make this a promising new procedure for the bromination of aromatic compounds.

Redox‐Divergent Construction of (Dihydro)thiophenes with DMSO

“…This suggests that diene 5 a might be an intermediate for the formation thiophene 2 a . According to previous reports, [24, 26] DMSO could react with HBr to produce dimethyl sulfide (DMS) and Br 2 . To test such process whether occurred in this protocol or not, the reaction between diene 5 a and DMS in the presence of Br 2 was conducted (Scheme 5 b).…”

Recent Advances in Bromination of Aromatic and Heteroaromatic Compounds

“…DMSO is available and cheap and can oxidize HBr. [122][123][124] This method was found to be suitable for electron-rich substrates. In particular, a convenient method using a mixture of equal volumes of DMSO and concentrated HBr was proposed for the bromination of various alkyl-substituted anilines and pyrroles containing an electron-accepting substituent in the 2-position.…”

“…In particular, a convenient method using a mixture of equal volumes of DMSO and concentrated HBr was proposed for the bromination of various alkyl-substituted anilines and pyrroles containing an electron-accepting substituent in the 2-position. 123 Significant excesses of the reagents were used. However, mono-or dibromoanilines were isolated in high yields depending on the reaction temperature and time.…”

Electrochemical Umpolung of Bromide: Transition-Metal-Free Bromination of Indole C–H Bond

“…Aromatic bromides are an important class of compounds, which are commonly utilized as the coupling partner in transition-metal-catalyzed cross-coupling reactions [ 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 ]. Thus, the development of a synthetic method of arylbromides has attracted tremendous efforts [ 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 , 76 , 77 , 78 , 79 , 80 , 81 , 82 ]. Among them, much progress has been made on palladium-catalyzed regioselective bromination of C–H bonds using different agents.…”