Advances in the application of NBS (N-brominated diamide) in organic reactions

related topicsNBS brominated
reagents
and brominated reactions N-brominated diamide (NBS) are commonly used in
organic
reactions, in recent years in a variety of organic reaction applications have made new research progress. The latest research results as catalysts, oxidants, selective bromine substitutes and polymer reaction triggers in the reaction process are reviewed.The traditional applications of N-bromide diamide (NBS) reagents in organic reactions are acrylic hydrogen, penicillin, and bromine generation of niobium-alpha;-bit hydrogen, known as Wol-Ziegler reactions. With the deepening of research, it is found that NBS can also be well applied as a catalyst, oxidant and so on, showing the great application value and potential of NBS reagents.NBS as a catalyst organamine and olefin catalytic addition to produce nitrogen-containing organic
compounds
is of great significance for basic research and is also important for chemical production. However, traditional reaction catalysts are often difficult to synthesize, expensive, and demanding to use. Sudalai and so on to NBS as a catalyst, toluene sulfonamide, alcohol as a pro-nuclear reagent in mild conditions to react to the active styrene amino, alkygen derivatives. The yield of both types of reactions is very high, and 100% use Mars plus.2 NBS as an oxidant the oxidation of secondary alcohols to ketones is a very important organic synthesis step, Sharma and other reports can use NBS to oxidize many secondary alcohols into ketones. The reaction is based on the cobalt complement of acetyl acetone as a catalyst (Eq. 3). The reaction condition is mild and the yield is high, but this method is not applicable to the chemicalization of level 1 alcohol, the reaction structure infers as shown in Figure 4. The production of bromine free fundamentals is the key.3 NBS reaction green chemical directionNBS free-based bromide reaction is usually carbon tetrachloride as a solvent, and known carbon tetrachloride on the ozone layer has a lot of damage, so its application is subject to many restrictions, so it is necessary to explore NBS bromide reaction conditions, to find alternatives to carbon tetrachloride. One of the solvent - free solidification should be a lot of research.application of 4 NBS in polymer research active polymerization is a very important method for preparing polymers with specific structures
narrow
molecules. Because the N-Br bond in NBS is very active, it is easy to break in the case of
heating
to obtain the active butylamide free agent and the inert bromine free agent on free fundamentals. It is also possible to use NBS as a chain of free fundamental polymerization to trigger transfer terminators. Percec used NBS as a trigger to polymerized the free-agent activity of vinyl chloride with TiCp2Cl2 as a catalyst.5 NBS research progress on the replacement of ketone's niobium-based neighbor hydrogen NBS is a very good niobium-alpha;-bit bromide substitute, the reaction is easy to operate, widely used. In order to improve the rate and yield of the reaction, many catalytic systems have been developed accordingly.other reactions involving 6 NBS Zoller, etc.) cite a route that converts penicillin into penicillin under neutral conditions to re-use this reaction with solids, which will remain on the reaction resin, excess reactants and other products (
DMSO
and butydiomine) that can be washed away with waterless solvents.NBS is now more and more widely used in organic reaction, and more and more applications. The development of new application areas, the study of reaction theory and the use of highly efficient catalysts are the main trends of NBS application research in organic reaction.