N-溴丁二酰亚胺／吡啶氧化合成己二酰基双偶氮化合物

以己二酰二氯和不同取代基的苯肼合成了N,N'-二芳基己二酰二肼类中间体,然后在N-溴丁二酰亚胺(NBS)／吡啶氧化体系下室温合成了8种己二酰基双偶氮化合物。第一步反应条件为:n(己二酰二氯):n(取代苯肼)=1:2,反应温度0-5℃,反应时间4 h,收率80%-93％;第二步反应条件为:n(N,N’-二芳基己二酰二肼):n(NBs／吡啶)=1:2,氧化反应时间0．5-1．0 h,收率80%-94%。并用元素分析、IR、1H NMR对合成的中间产物及目标化合物进行了表征。     

A simple,economical, and catalyst-free oxidation of thiols to disulfides

A simple, rapid, and highly efficient method for the preparation of symmetrical aliphatic, aromatic, and heteroaromatic disulfides is reported. Addition of NBS to an alkyl- or arylthiol under catalyst-free conditions in dichloromethane solution produces the corresponding disulfides in nearly quantitative yields.     

苯偶姻氧化反应的研究

三溴化苯基三甲铵和Ｎ－溴代丁二酰亚胺与苯偶姻反应，得到氧化产物苯偶酰．提出了反应机理．证实了三溴化苯基三甲铵和Ｎ－溴代丁二酰亚胺，在苯偶姻氧化反应中，反应条件温和，产率高，是实用的由苯偶姻制备苯偶酰的途径．     

Synthesis of surfactants from 1-olefins wo bromoalkoxylation reaction

Alkyl β-bromoalkyl ether derivatives (I) (isomeric mixture) were prepared by the bromoalkoxylation reaction of olefins withN-bromosuccinimide (NBS) and appropriate alcohols. A series of nonionic surfactants was obtained by the reaction of I with glycols or ethanolamines. The distribution of two isomers (Markovnikov-type and anti-Markovnikov-type) in products was found to be slightly different from that in the starting material (I). Surface properties of several nonionic surfactants, which were prepared from I, were presented and discussed based on the difference in the structures.     

N-溴代丁二酰亚胺在有机反应中的研究进展

综述了N-溴代丁二酰亚胺的合成方法并进行了简要的评价。着重介绍了N-溴代丁二酰亚胺应用于烯丙位苄位的溴代反应;酮、芳香化合物或杂环化合物的亲电溴化反应;烯烃的加成反应;以及其作为催化剂、氧化剂等方面的研究。     

New route for bromination of multiwalled carbon nanotubes under mild and efficient conditions

A short study on bromination of multiwalled carbon nanotubes (MWCNTs) through new and convenient methods was reported. Bromine (Br) is chemically attached on MWCNTs surfaces through electrophilic addition and radical reactions using N-Bromosuccinimide (NBS), NH₄NO₃/NBS and Br₂ under thermal and UV conditions. Functionalized CNTs with Bromine groups, were characterized by Fourier transform infrared spectroscopy (FTIR), thermo gravimetric analysis (TGA), scanning electron microscopy and X-ray diffraction (XRD) methods.     

New application of cross-linked poly(N-bromoacrylamide) and poly(N-bromosuccinimide) as highly efficient and chemoselective heterogeneous polymeric catalysts for deprotection of 1,3-dithianes and 1,3-dithiolanes under mild conditions

Cross-linked poly(N-bromoacrylamide) (PNBA) and poly(N- bromosuccinimide) as the mild and efficient heterogeneous polymeric catalysts were applied for selective deprotection of 1,3-dithianes and 1,3-dithiolanes to their corresponding carbonyl compounds. They were also effective as a reagent in aqueous media. These methods are very simple and the polymer catalysts could be recycled several times. Deprotection of thioacetal and thioketal without enolizable hydrogens proceeded very well to give only the corresponding aldehyde and ketone in high to excellent yield. Nevertheless, in the case of thioketals carrying enolizable hydrogens, deprotection accompanied with the formation of a minor ring-expanded product is observed. However, using the PNBA/H₂O system, ring expansion of these thiolketals with enolizable hydrogen was not detected. These methods provide advantages, such as chemoselectivity, easy preparation, simple work up, excellent yields, and the ability to recycle the catalyst, which makes this method more useful compared to other known methodologies.     

6-氨基-5-溴喹喔啉的溴化合成

该文提出以1,3-二溴-5,5-二甲基海因作为溴化剂合成6-氨基-5-溴喹喔啉的方法。分别以1,3-二溴-5,5-二甲基海因、N-溴代丁二酰亚胺和液溴作为溴化剂,考察了温度、溶剂和反应时间对溴化反应的影响,确定了最佳反应条件:n(1,3-二溴-5,5-二甲基海因)∶n(6-氨基喹喔啉)=1.0∶2.0,反应温度20℃,以二氯甲烷为溶剂,反应时间2 h。在该反应条件下,5-溴-6-氨基喹喔啉的溴化收率达97.6%。该方法反应条件温和,步骤精简,无溴化杂质生成,并以高收率达到医用原料的要求。现已完成10 kg级扩试。     

N-溴代丁二酰亚胺绿色合成工艺条件的探究

以溴酸钠、溴化钠、硫酸、丁二酰亚胺为主要原料,研究了N-溴代丁二酰亚胺(NBS)的绿色化合成工艺。优化工艺条件为:原料配比n(溴酸钠)∶n(溴化钠)∶n(硫酸)∶n(丁二酰亚胺)=1∶2∶1.7∶2.6,溶剂水90 mL,反应温度为20~40℃,反应时间为2.5 h,此条件下产品收率87%,有效溴含量为44.3%,纯度98.6%。     

An efficient one-step cyclization of thiobenzanilides to benzothiazoles: using N-bromosuccinimide under mild conditions

Benzothiazoles were readily prepared in one step from thiobenzanilides using N-bromosuccinimide in CH₂Cl₂–CCl₄ (1:1 V/V) at room temperature, with good yields under mild reaction conditions.