Palladium-Catalyzed Cross-Coupling of Aryl Chlorides and Triflates with Sodium Cyanate: A Practical Synthesis of Unsymmetrical Ureas
作者:Ekaterina V. Vinogradova、Brett P. Fors、Stephen L. Buchwald
DOI:10.1021/ja305212v
日期:2012.7.11
chlorides and triflates with sodium cyanate is reported. The protocol allows for the synthesis of unsymmetrical N,N'-di- and N,N,N'-trisubstituted ureas in one pot and is tolerant of a wide range of functional groups. Insight into the mechanism of aryl isocyanate formation was gleaned through studies of the transmetalation and reductive elimination steps of the reaction, including the first demonstration
报道了一种钯催化芳基氯和三氟甲磺酸酯与氰酸钠交叉偶联的有效方法。该协议允许在一锅中合成不对称的 N,N'-di-和 N,N,N'-三取代脲,并且可以容忍多种功能组。通过对反应的金属转移和还原消除步骤的研究,包括从芳基钯异氰酸酯络合物中还原消除生成异氰酸芳基酯的首次演示,深入了解了芳基异氰酸酯的形成机制。