Jun 10, 2011 · NBS is used as a substitute for Br 2 in these cases since Br 2 tends to react with double bonds to form dibromides. The advantage of NBS is that it provides a low-level concentration of Br 2 , and bromination of the double bond doesn’t compete as much.

NBS was usually used in an acidic condition (AcOH–H 2 O) and inevitably produced the corresponding stoichiometric succinimide byproduct that required immediate elimination by column purification. Therefore, a green catalytic protocol is highly desirable.

May 5, 2017 · With NBS/$\ce {CCl4}$ allylic bromination occurs. But with NBS/$\ce {AcOH}$ bromination occurs on the alkene double bond. Why does this difference occur and how? I.e what will be the mechanisms of both?

Apr 23, 2023 · The procedure utilizes N-Bromo succinimide (NBS) as a typical brominating agent in refluxing carbon tetrachloride (CCl 4) in the presence of a radical initiator such as dibenzoyl peroxide [C 6 H 5­ CO-OO-COC 6 H 5], di-t-butylperoxide [(CH 3) 3 C-OO-C(CH 3) 3], 2,2’-azobis(isobutyronitrile) [AIBN].

Instead of Br 2, one can use a similar source of electrophilic bromine like N-bromosuccinimide (NBS). Various acids can be used (e.g. HBr, acetic acid (AcOH). Examples: Notes: Example 1 shows formation of a new C-Br bond using HBr and Br2. …

N-chloro- (NCS), N-bromo- (NBS) and N-iodosuccinimide (NIS) were selected as halogen atom transfer reagents, while the list of environmentally accepted solvents [3,4,5,6,7] from aprotic Solkane TM 365 to Me-THF, protic MeOH and AcOH, and finally water was chosen as reaction medium candidates.

N -Bromosuccinimide (NBS) is a brominating and oxidizing agent that is used as source for bromine in radical reactions (for example: allylic brominations) and various electrophilic additions.

Our protocol (oxone-halide) can eliminate not only the use of hazardous oxidants (e.g., Pb(OAc)4, CrO3, OsO4, t-BuOCl, NBS, and m-CPBA, etc) but also the production of organic byproducts or toxic...

Bromination of 2,5-bis (2-thienyl)pyrrole with NBS in AcOH–THF prefers the β-position of pyrrole over the α-position of thiophene. A DFT study and experiments in different solvent systems suggest the important role of the solvent in tuning the selectivity.

Apr 15, 2019 · The role of NH 4 OAc was to produce, in the presence of NBS, AcOH and HBr, which then polarize the N-Br bond facilitating the para-bromination of the aromatic system.