A versatile catalyst for Heck reactions of aryl chlorides and aryl bromides under mild conditions

In the presence of Cy2NMe, PdlP(t-Bu)(3) serves as an exceptionally mild an d versatile catalyst for Heck reactions of aryl chlorides and bromides. A s terically and electronically diverse array of aryl bromides, as well as act ivated aryl chlorides, couple with a range of mono- and disubstituted olefi ns at room temperature, furnishing the arylated product with high E/Z stere oselection. The corresponding reactions of a broad spectrum of electron-neu tral and electron-rich aryl chlorides proceed at elevated temperature, also with high selectivity. In terms of scope and mildness, Pd/P(t-Bu)(3)/Cy2NM e represents an advance over previously reported catalysts for these Heck c oupling processes.