Bromination of Deactivated Aromatic Compounds with Sodium Bromide/Sodium Periodate under Mild Acidic Conditions

Abstract

A new, simple, and practical aromatic bromination process is disclosed wherein NaBr/NaIO4 combination in acidic medium was efficiently utilized for the first time in the bromination of deactivated aromatic compounds, thus, affording the corresponding bromo-derivatives of deactivated aromatics in good yields and purity.

Effect of emulsifier content on the rheological properties of asphalt emulsion residues

“…Asphalt emulsions are obtained by dispersing asphalt globules in water with an emulsifying agent. They have been used for various surface treatments such as the traditional chip seals to construction of new pavements for low volume roads . To improve their performance, different additives were added into the emulsions, such as polymer latex.…”

Recent Update on Transition Metal‐Free C(sp2)−H Bond Halogenation in (Hetero) Arenes

“…Dai et al in 2014 developed an efficient brominating methodology [32] on aromatic amines under mild conditions using DMSO/HBr system. Different aromatic derivatives (29) have been investigated under the protocol (Scheme 19). This methodology was also extended to carbazole and pyrrole derivatives.…”

“…EBMIDTB [18] HBr,O 2, Visible light, Acr + -Mes [21] NaBr Oxone [26] , mechanical ball milling K 2 S 2 O 8 [16] NaCl or NH 4 Cl PyrBr 3 (pyridinium tribromide) [67] 2-MePyNO 3 HBr [20] air NBS [62] /Silica HX/ Alkylammonium nitrates or HX/3-methyl-1-(butyl-4-sulfonyl) Imidazolium Nitrate [48] X=Cl/Br NXS (X=Cl/Br) [71] DMSO/HX (X=Br/I) [73] NaBr-NaIO 4 [29] NH 4 X/H 2 O 2 [70] X=Br/I pyridinium bromide [65] H 2 O 2 /p-TSA TsNBr 2 [28] H 5 IO 6 [47] /NaX (X=Br,I) DXH [94] X=Cl/Br/I Electrochemical [95] NIS,Na 2 CO 3 [42] TBBDA or PBBS [27] NH 4 Br [31] Oxone…”

Recent Advances in Bromination of Aromatic and Heteroaromatic Compounds

“…The combination of NaBr and NaIO 4 in dilute aqueous H 2 SO 4 (~1:1) was reported to monobrominate unreactive substrates, such as chloro-, nitro-, and dinitrobenzene, benzoic acid, and o-and m-nitrobenzaldehydes, in high yields. 120 The use of iodine(V) oxide as an oxidant in combination with KBr was also proposed. High yields were obtained for the monobromination of anisole derivatives substituted with various electron-accepting substituents (Scheme 70).…”