| The aminohalogenation is a reaction for the converting common petroleum olefins into vicinal haloamine products by the addition of amine and halogen moieties onto carbon-arbon double bonds. The animobrominationare important building blocks in organic and medicinal chemistry, because they can be easily converted into amino acids or aziridinecarboxylates by replacement of the halogen in both nucleophilic substituentional reaction of intermolecular or intramolecular, May be further converted into numerous useful functional groups, such as the alkamine, diethylenetriamine, etc.It is also of considerable significance, which vicinal haloamino products are relatively research on biochemical and drug chemical as well as pharmaceutical molecular synthesis. The synthesis and nature research of vicinal haloamino product become an active research field in the world. Meanwhile, the confusing mechanism hypothesis of the original aminohalogenation may also have attributed to this situation.Recently,researchers are interested in the topics as follow so far:1. The firstis exploring new catalysts.2. The second is expanding substrate scopes.3.The third is screeningvariousnitrogen/halogensources.Reportedolefin substrates of aminohalogenati on are simple olefins, α,β-unsaturated ketones, cinnamates, nitrostyrenes and unsaturated nitriles,etc. More reserches lie on the Simple olefins, unsaturated ester, unsaturated ketones, and less on the study of unsaturated vinyl nitrobenzene.While β-nitrobenzene is one of the useful substrates for olefin addition reaction, and it plays a important role in the chemistry and biologywhich cause our research interest.Now, the halogen/nitrogen sources which used in aminohalogenation are divided into two groups by the reported articals.The first is the combination of N-bromosuccinimide and p-toluenesulfonamide.The secondis N, N-dichlorotoluenesulfonamide, N-bromoacetamide.Based on 1,3-Dibromo-5,5-dimethylhydantoin (DBDMH) the highly active bromine and its samiliar structure with N-bromoacetamide, this paper puts forward to DBDMH as the halogen/nitrogen sources,β-nitrobenzene derivatives as substrates, developed a newaminobromination system.The first chapter is a summary on researching progress of the aminohalogenation. It contains halogen and nitrogen sources, catalyst, the substrates study condition of aminobromination reaction at various systems.In the chapter Ⅱ, a new systematic protocol for the high regioselective aminobromination of β-nitrostyrene derivatives with 1,3-Dibromo-5,5-dimethyl Hydantoin (DBDMH) as nitrogen/bromine sources has been developed. Two kinds of β-nitrostyrene derivatives give different reaction results under different reaction conditions. For the β-nitrostyrene derivatives, thisprotocol offered vicinal haloamine products in good to excellent yields(up to 96%) at room temperature in CH3CN catalyzed by Na2CO3. For the β-methyl-β-nitrostyrene, the good to excellent yields(up to 95%)were also achieved refluxed in CH3CN catalyzed by KOH. The strong electron-donating substituents (e.g., OCH3) on the 4-position of benzene ring could deactivated the reaction activity of β-nitrostyrene derivetives with DBDMH, however, it also afforded the vicinal haloamines as the sole adductive product. Whereas strong electron-withdrawing substituent (e.g., NO2) could activated reaction activity of them remarkably and afforded the vicinal haloamines as the sole adductive product, too. The result revealed that the addition reaction has a nucleophilic addition feature. The aminobromination of 20 examples of β-nitrostyrenes have been investigated in this work and the structure of all products were confirmed by their corresponding 1H NMR, 13C NMR spectra and HRMS(ESI). A possible path way involving a nucleophilic conjugate addition was proposed. |
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