The palladium-salen complex palladium(Ⅱ) N,N'-bis{[5-(triphenylphosphonium)-methyl]salicylidene}-1,2-ethanediamine chloride was found to be a highly active catalyst for the copper- and solvent-free coupling react...The palladium-salen complex palladium(Ⅱ) N,N'-bis{[5-(triphenylphosphonium)-methyl]salicylidene}-1,2-ethanediamine chloride was found to be a highly active catalyst for the copper- and solvent-free coupling reaction of terminal alkynes with different acyl chlorides in the presence of triethylamine as base,giving excellent ynones under aerobic conditions.展开更多
An efficient palladium-catalyzed copper- and amine-free Sonogashira coupling reaction of aryl bromides and chlorides was studied using a sterically hindered monooxychlorophosphine as new ligand.The use of 2 mol%Pd（OA...An efficient palladium-catalyzed copper- and amine-free Sonogashira coupling reaction of aryl bromides and chlorides was studied using a sterically hindered monooxychlorophosphine as new ligand.The use of 2 mol%Pd（OAc）_2 in the presence of K_2CO_3 allows the coupling reaction to proceed at mild condition with good to excellent yields.展开更多
碳氢化合物广泛存在于贫燃发动机尾气中,且原料易得无污染,以碳氢化合物为还原剂选择性催化还原NO x在富氧汽车尾气处理上具有一定的现实意义和应用前景。金属负载分子筛脱除NO x具有活性高及对环境友好等优点。本文综述了Fe、Co、In、M...碳氢化合物广泛存在于贫燃发动机尾气中,且原料易得无污染,以碳氢化合物为还原剂选择性催化还原NO x在富氧汽车尾气处理上具有一定的现实意义和应用前景。金属负载分子筛脱除NO x具有活性高及对环境友好等优点。本文综述了Fe、Co、In、Mn、Pd等非Cu基金属负载分子筛上碳氢化合物选择性催化还原NO x反应机理和催化剂性能等方面的研究进展,并在归纳和总结已有研究成果的基础上展望了非Cu基负载分子筛的研究发展趋势。依据负载金属、分子筛和还原剂不同,碳氢化合物选择性催化还原氮氧化物的活性位和反应中间体也各不相同,以丙烷为还原剂时Fe-ZSM-5分子筛是通过孤立的Fe2+与Fe3+之间的价态变化来脱除氮氧化物,而以甲烷为还原剂时Fe-AlPO-5分子筛则是以孤立的Fe3+和低聚态的Fe x O y物种为活性位。甲烷广泛存在于贫燃发动机尾气中,是脱除氮氧化物的较佳还原剂,而乙烯和丙烷等烃类由于其还原温度低于甲烷也得到较多研究。对其反应机理的研究有助于寻找影响反应的关键因素从而改善催化剂性能。根据所负载金属、分子筛和还原剂的特点,可优化出高效且环境友好的脱硝催化剂体系。展开更多
基金the Research Council of Shahrood University of Technology for the support of this work
文摘The palladium-salen complex palladium(Ⅱ) N,N'-bis{[5-(triphenylphosphonium)-methyl]salicylidene}-1,2-ethanediamine chloride was found to be a highly active catalyst for the copper- and solvent-free coupling reaction of terminal alkynes with different acyl chlorides in the presence of triethylamine as base,giving excellent ynones under aerobic conditions.
基金Henan University of Technology for financial support(The Introduction of Talent Fund)
文摘An efficient palladium-catalyzed copper- and amine-free Sonogashira coupling reaction of aryl bromides and chlorides was studied using a sterically hindered monooxychlorophosphine as new ligand.The use of 2 mol%Pd（OAc）_2 in the presence of K_2CO_3 allows the coupling reaction to proceed at mild condition with good to excellent yields.
文摘碳氢化合物广泛存在于贫燃发动机尾气中,且原料易得无污染,以碳氢化合物为还原剂选择性催化还原NO x在富氧汽车尾气处理上具有一定的现实意义和应用前景。金属负载分子筛脱除NO x具有活性高及对环境友好等优点。本文综述了Fe、Co、In、Mn、Pd等非Cu基金属负载分子筛上碳氢化合物选择性催化还原NO x反应机理和催化剂性能等方面的研究进展,并在归纳和总结已有研究成果的基础上展望了非Cu基负载分子筛的研究发展趋势。依据负载金属、分子筛和还原剂不同,碳氢化合物选择性催化还原氮氧化物的活性位和反应中间体也各不相同,以丙烷为还原剂时Fe-ZSM-5分子筛是通过孤立的Fe2+与Fe3+之间的价态变化来脱除氮氧化物,而以甲烷为还原剂时Fe-AlPO-5分子筛则是以孤立的Fe3+和低聚态的Fe x O y物种为活性位。甲烷广泛存在于贫燃发动机尾气中,是脱除氮氧化物的较佳还原剂,而乙烯和丙烷等烃类由于其还原温度低于甲烷也得到较多研究。对其反应机理的研究有助于寻找影响反应的关键因素从而改善催化剂性能。根据所负载金属、分子筛和还原剂的特点,可优化出高效且环境友好的脱硝催化剂体系。
