Extremely Efficient Cross-Coupling of Benzylic Halides with Aryltitanium Tris(isopropoxide) Catalyzed by Low Loadings of a Simple Palladium(II) Acetate/Tris(p-tolyl)phosphine System
作者:Chi-Ren Chen、Shuangliu Zhou、Deepak Baburao Biradar、Han-Mou Gau
DOI:10.1002/adsc.201000311
日期:——
Highly efficient coupling reactions of benzylic bromides or chlorides with aryltitanium tris(isopropoxide) [ArTi(O‐i‐Pr)3] catalyzed by a simple palladium(II) acetate/tris(p‐tolyl)phosphine [Pd(OAc)2/ P(p‐tolyl)3] system are reported. The coupling reactions proceed in general at room temperature employing low catalyst loadings of 0.02 to 0.2 mol%, affording coupling products in excellent yields of
苄型溴化物或氯化物与aryltitanium三(异丙醇)的高效率的偶联反应[ARTI(O-异PR)3 ]通过简单的钯(II),乙酸/三(催化p -甲苯基)膦[将Pd(OAc)2 /报告了P(p -tolyl)3 ]系统。偶联反应通常在室温下进行,使用0.02至0.2mol%的低催化剂负载量,以高达99%的优异产率提供偶联产物。对于带有强吸电子氰基(CN)或三氟甲基(CF 3)取代基,该反应需要更高的催化剂负载量为1 mol%,或者该反应在60°C下进行。催化系统还可以耐受带有1个氢原子的(1-溴乙基)苯,同时使用1 mol%的催化剂负载量,以70%的收率获得偶联产物。