可以通过将1-硫代丁二烯衍生物直接加到异氰酸N-芳基酯和N-烷基N-烷基酯上来简明地以高收率制备立体确定的多取代的二烯酰胺。这些二烯酰胺的亲电环化反应以极好的收率和完美的选择性生成了取代的环状亚氨基醚。当用12 N HCl水溶液处理时,二烯酰胺经过有效且选择性的亲电环化,得到环状亚氨酸酯衍生物。当用NBS处理时,形成单溴或双溴的环状亚氨基醚。
可以通过将1-硫代丁二烯衍生物直接加到异氰酸N-芳基酯和N-烷基N-烷基酯上来简明地以高收率制备立体确定的多取代的二烯酰胺。这些二烯酰胺的亲电环化反应以极好的收率和完美的选择性生成了取代的环状亚氨基醚。当用12 N HCl水溶液处理时,二烯酰胺经过有效且选择性的亲电环化,得到环状亚氨酸酯衍生物。当用NBS处理时,形成单溴或双溴的环状亚氨基醚。
Lewis acid-controlled reactions of zirconacyclopentadienes with isocyanates and isothiocyanates. One-pot three- or four-component synthesis of multiply substituted iminocyclopentadienes and butadiene-tethered 1,6-bisamides and electrophilic cyclization
作者:Qiaoshu Hu、Jiang Lu、Congyang Wang、Chao Wang、Zhenfeng Xi
DOI:10.1016/j.tet.2007.02.015
日期:2007.7
products in high isolated yields from the reactions of zirconacyclopentadienes with isocyanates, depending on the substituents of isocyanates. The reactionpath and products could be controlled by Lewis acids. As a demonstration of the usefulness of thus obtained unsaturated bisamides, electrophilic cyclization using acids, NBS, and I2 was carried out. Electrophilic cyclization of multisubstituted conjugated
Lewis acid-promoted reactions of zirconacyclopentadienes with isocyanates. A one-pot three-component synthesis of multiply-substituted iminocyclopentadienes from one isocyanate and two alkynes
作者:Jiang Lu、Guoliang Mao、Wenxiong Zhang、Zhenfeng Xi
DOI:10.1039/b509142j
日期:——
Multiply-substituted iminocyclopentadienes were formed from Lewis acid-promoted reactions of zirconacyclopentadienes and isocyanates via a one-pot three-component coupling process; the C=O double bond of the RN=C=O moiety in the isocyanate was cleaved, and the isocyanates behaved formally as a one-carbon unit with Lewis acid-dependent and substituent-dependent reactions being realized.
多价取代的亚氨基环戊二烯是由路易斯酸促进的氧化锆环戊二烯与异氰酸酯的反应通过一锅三组分偶联过程形成的;异氰酸酯中的RN = C = O部分的C = O双键被裂解,并且异氰酸酯在形式上表现为单碳单元,实现了路易斯酸依赖性和取代基依赖性反应。
Preparation and Electrophilic Cyclization of Multisubstituted Dienamides Leading to Cyclic Iminoethers
作者:Congyang Wang、Jiang Lu、Guoliang Mao、Zhenfeng Xi
DOI:10.1021/jo050433q
日期:2005.6.1
Stereodefined multisubstituted dienamides could be concisely prepared in high yields by direct addition of 1-lithiobutadiene derivatives to both N-aryl and N-alkyl isocyanates. Electrophilic cyclization of these dienamides was achieved to generate substituted cyclic iminoethers in excellent yields with perfect selectivity. When treated with 12 N aqueous HCl, dienamides underwent efficient and selective
可以通过将1-硫代丁二烯衍生物直接加到异氰酸N-芳基酯和N-烷基N-烷基酯上来简明地以高收率制备立体确定的多取代的二烯酰胺。这些二烯酰胺的亲电环化反应以极好的收率和完美的选择性生成了取代的环状亚氨基醚。当用12 N HCl水溶液处理时,二烯酰胺经过有效且选择性的亲电环化,得到环状亚氨酸酯衍生物。当用NBS处理时,形成单溴或双溴的环状亚氨基醚。