光气检测用小分子荧光探针的研究进展

光气因其剧毒性对社会公共安全和人类健康造成巨大威胁,对其实时监测、检测十分必要。荧光探针因具有选择性好、灵敏度高、可实时监测、成本低、操作简单等优点已成为识别光气分子的有力工具。首先,综述了光气小分子荧光探针的研究进展;然后,以荧光分子的识别基团为分类标准,从设计思路和识别机理对各类荧光探针进行了归纳和总结;最后,对光气小分子荧光探针的发展方向及其所面临的挑战进行了展望。     

便携式气质联用仪在环境污染事故应急监测中的一个应用实例

HAPSITE是一台便携式气质联用仪（GC-MS）,体积小、易携带,便于进行环境污染事故现场监测,适合于分析大气中或水中的挥发性有机物,在国内已被成功用于多起现场环境应急监测工作中。2010年5月图们市内山上发现埋藏的旧钢瓶导致了民众中毒突发事件,用HAPSITE快速检测出钢瓶内的挥发性有机污染物主要是光气,为很好解决这次环境污染事故提供了重要依据     

Direct dyes containing two urea groups

J-acid and γ-acid were condensed with tolueneisocyanate to prepare new coupling components , containing two urea groups, with similar properties to those of the known J-acid urea. The diurea dyes obtained from the new intermediates show similar properties to those of conventional phosgenated direct dyes.     

碳酸二甲酯的合成方法及发展趋势

概述了碳酸二甲酯的合成方法和研究现状、以及合成技术中存在的问题,展望了碳酸二甲酯的发展趋势。     

替代光气进行有机合成的化学方法

综述了目前取代剧毒原料光气进行有机合战的12种有价值的绿色化学方法，以典型的合成路线为基础．介绍了其优缺点、发展现状及存在的问题，得出结论：碳酸二甲酯的方法是当前最为廉价且已有大规模生产的方法．三光气、碳酸乙烯酯取代光气也取得了一定的成绩，而一氧化碳羟基化有很好的前景．但需在催化剂方面作进一步研究。     

Towards a Phosgene-Free Synthesis of Aryl Isocyanates: Alcoholysis of <Emphasis Type="Italic">N-</Emphasis>phenylurea to <Emphasis Type="Italic">N-</Emphasis>phenyl-<Emphasis Type="Italic">O-</Emphasis>methyl Carbamate Promoted by Basic Metal Oxide Nanoparticles and Organocatalysts

There is an urgent need to develop new processes for the synthesis of polyurethanes and polycarbonates different from the current technology based on the use of phosgene. In the case of polyurethanes, the reaction of phosgene with aromatic amines renders N-aryl isocyanates that are the co-monomers for these polymers. In the search for a phosgene-free process for the synthesis of N-aryl isocyanates, N-aryl carbamates could play a key role of synthetic precursors. N-Aryl carbamates can be prepared in turn by alcoholysis of N-aryl ureas. Herein, we compare the catalytic activity of three homogeneous catalysts and four heterogeneous metal oxides for the methanolysis of N-phenylurea as a model probe for other aromatic ureas. In the present work we have carried out this reaction in the presence of KOH, 1,8-diaminonaphthalene (a protonic sponge), a dimeric phosphazene (strong, neutral soluble base) and nanometric ZnO, MgO, CaO and a mixed Mg/Al metal oxide derived from hydrotalcite calcination. Besides the target N-phenyl O-methyl carbamate, N-phenyl isocyanate and undesired aniline were also formed. It was observed that using KOH and diaminonaphthalene, aniline was formed preferentially with respect to the desired carbamate. In contrast, dimeric phosphazene forms the target N-phenyl O-methyl carbamate with 90% selectivity at 99% N-phenylurea conversion. In the case of the metal oxides, the best-performing solid catalyst was CaO that exhibits similar activity (99% N-phenylurea conversion) and carbamate selectivity (89%) as phosphazene. CaO performs as a truly heterogeneous catalyst and could be reused for a second run with only a 4 and 2% decrease in conversion and selectivity, respectively.