Stable Polymer-Bound Iodine Azide

1,2-Azido-iodination of a wide range of alkenes under very mild conditions can be achieved by using a novel iodate(I ) reagent, a stable and storable polymer-bound iodine azide, which is available in two steps (see scheme). Simple work-up and convenient use in automated parallel synthesis are important features of this polymer-bound reagent.     

The Chemistry of Iodine Azide

Whereas chlorine azide and, to a lesser extent, bromine azide have long been used as preparative reagents in spite of their explosive nature, little is known about the properties of iodine azide although it was actually discovered before the other two compounds. Hantzsch's warning to beware fo this material, uttered in 1900, still seems to be widely observed. Only recently has iodine azide been isolated as a pure substance, thus promoting its more detailed investigation. Proper use of this highly labile reagent opens up new vistas in synthetic chemistry.     

Photochemical Transformations with Iodine Azide after Release from an Ion‐Exchange Resin

This report discloses the photochemical homolytic cleavage of iodine azide after its formation following release from polymer‐bound bisazido iodate(I) anions. A series of radical reactions are reported including the 1,2‐functionlization of alkenes and the unprecedented chemoselective oxidation of secondary alcohols in the presence of primary alcohols.     

催化动力学库仑滴定法测定6-巯基嘌呤

本文首次报道用催化动力学和库仑分析相结合的方法测定抗癌药物乐疾宁中的主要成份6-巯基嘌呤(6-MP)。此法基于测定与催化剂(或称诱导剂)6-MP浓度成正比的库仑池反应诱导期(从接通电源到指示电流突然增大到指定值的毫库仑数),从而求出催化剂6-MP的量。本法具有库仑分析法与催化动力学分析法的优点即准确、灵敏、快迅和简便。方法线性范围为1.47×10~(-7)～5.29×10~(-6)mol/L。应用于药物乐疾宁中6-MP的测定,回收率为95%～103%,结果满意。     

Ab initio Study of Energetic Solids: Cupric Azide,Mercuric Azide,and Lead Azide

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.     

Enantioselective Addition of Iodine Azide to α,β-Unsaturated Carboxylic Acid Derivatives

The addition of iodine azide to chiral conjugated N-enoyl-sultam or α,β-unsaturated N-acyloxazolidinones generated two asymmetric centers at C(α) and C(β) with high π-face differentiation and regioselectivity. The diastereomerically pure product was easily obtained by crystallization with purity up to 94% de. The structure of 2a was determined by X-ray diffraction analysis which also indicated that B and 4 are reactive conformations.     

Spectrophotometric Determination of Azide Ion Through Carbon Disulphide - Azide Reaction

Abstract

The azide ion can be converted quantitatively into 1,2,3,4, - thiatriazol - 5 - thiolate ion by treatment with carbon disulphide in aqueous ethanolic medium. The CS₂N₃ ^? concentration is measured spectrophotometrically at 321nm, where ?= 7. 8 × 10³ l mol^?1 cm^?1. The conditions outlined below provide a rapid, simple and precise method to determine the azide ion at the 8 μg/ml level.The influence of several foreign ions on the proposed method is also studied.     

New Hydrazinium Azide Compounds

The synthesis and characterization of several azide salts of organic hydrazinium derivatives is reported. The crystal structures of N‐amino‐1‐azoniacycloheptane azide, morpholinium azide, N,N‐dibenzylhydrazine and phenylhydrazinium azide phenylhydrazinate were determined. The thermal, shock and friction sensitivity of these compounds was investigated. For several compounds the products formed in the explosive decomposition were determined.     

叠氮聚合物的合成

叠氮基团不仅是高含能基团和高反应性基团,而且也可以被转化为其他官能基团。叠氮聚合物可用作高能黏合剂、交联材料以及表面改性材料等,还可以作为合成功能高分子的前体,因此叠氮聚合物的合成研究引起了高分子科学家的广泛关注。到目前为止,叠氮聚合物的合成方法研究取得了新的进展,主要包括: 高分子化学改性法、环醚类叠氮单体阳离子开环聚合法和不饱和叠氮单体自由基聚合法。本文综述了近些年来叠氮聚合物的合成研究方面取得的主要成果和进展,其中包括本课题组的一些研究工作。     

叠氮化氰的光解离机理

采用多参考态方法,在MRCI+Q//CAS(10,9)/6-311+G(2df)水平上对叠氮化氰(N3CN)的光解离机理进行理论研究.优化得到基态(S0)和低激发态(S1、S2、T1)势能面上的极小点、过渡态、内转换交叉点(IC-S1/S0)和隙间窜跃交叉点(ISC-S1/T1)的结构和能量,构建反应势能面.在MRCI+Q//CAS(10,9)水平上计算N3CN的垂直激发能,并和实验值进行对比.结果表明,在S0、S1、S2和T1态势能面上,N—N键断裂生成N2+NCN是主要解离途径,而C—N键断裂通道是次要通道.实验观测到220 nm处的吸收峰对应分子由S0态到S1态的激发,对应主要光解离产物为NCN[a1△g];而在275 nm处的吸收峰则对应分子被激发到T1态,然后直接生成基态产物NCN[X3Σg-].我们的理论结果与实验测量符合得很好.     

Azide rearrangements in electron-deficient systems

The azide group has a diverse and extensive role in organic chemistry, reflected in the power of azide anion as a strong nucleophile, the role of organic azides as excellent substrates for cycloaddition reactions, the uses of azides as precursors of amines and nitrenes, and azide rearrangements known as the Curtius and Schmidt reactions. In recent years the scope of the Schmidt reaction has begun to be explored in depth, so that it now represents an important reaction in synthetic chemistry. This tutorial review analyses and summarises key recent developments in the field of Schmidt reactions.     

Expedient Synthesis of t-Butyl Azide

A simple, economical synthesis of bulk (1 to 10,000 moles) quantities of t-butyl azide is described, utilizing only t-butyl alcohol, water, sodium azide, and sulfuric acid.     

Diazotransfer Reactions with p-Acetamidobenzenesulfonyl Azide

The utility of p-acetamidobenzenesulfonyl azide in diazotransfer reactions is described. This practical, cost effective reagent offers advantages over existing alternatives.     

Azide mit zwei verschiedenen Metallatomen

Crystal structures of azides containing two different metal atoms are discussed. Elements with higher electronegativity have the greatest influence on the structures. They form finite or infinite metal azide complexes, the degree of covalent binding betweenM(II) and azide groups raises with increasing ionisation potential of the metal, the stability of complex azides is not influenced seriously thereof. The arrangement ofM(I)-ions is influenced to a large extent by the stereochemistry. The azide groups are essentially asymmetrical with N-N-distances between 1.10 and 1.28 Å, the mean distance is 1.18 (3) Å. Azide groups are slightly bent [N-N-N=177 (5)°] and are always coordinated to several metal atoms. Frequently the central nitrogen atoms of azide groups are located closer toM(I)-ions than terminal nitrogens. Some complex azides contain water which is situated beside the azide groups within the coordination polyhedra.

     

Azide Ionic Liquids for Safe,Green, and Highly-Efficient Azidation Reactions to Produce Azide Polymers

Azide compounds are widely used and especially, polymers bearing pendant azide groups are highly desired in numerous fields. However, harsh reaction conditions are always mandatory to achieve full azidation, causing severe side reactions and degradation of the polymers. Herein, we report the design and preparation of two azide ionic liquids (AILs) with azide anion and triethylene glycol (E₃)-containing cation, [P_444E3][N₃] and [MIM_E3][N₃]. Compared with the traditional sodium azide (NaN₃) approach, both AILs showed much higher reaction rates and functional-group tolerance. More importantly, they could act as both reagents and solvents for the quantitative azidation of various polymeric precursors under mild conditions. Theoretical simulations suggested that the outstanding performance of AILs originated from the existence of ion pairs during the reaction, and the E₃ moieties played a crucial role. Lastly, after the reaction, the AILs could be easily regenerated, presenting a safer, greener, and highly efficient synthesis route for azide polymers.     

Azide synthesis with stable nitrosyl salts

Aryl and acyl hydrazines were converted to azides in excellent yields by an equimolar amount of nitrosyl tetrafluoroborate or nitrosyl sulfate.