钯催化芳基溴代物和氨基乙醛缩二乙醇的偶联反应研究

Study on the Cross-coupling of Aryl bromides with 2-Amino Acetaldehyde Diethyl Acetal under the Pd Catalyst

以Pd2(dba)3/XantPhos为原位生成的催化剂,研究了以芳基溴代物与氨基乙醛缩二乙醇之间的偶联反应合成N-(2,2-二乙氧基乙基)芳胺的反应,考察了催化剂前体、配体以及催化剂前体与配体的用量对该反应的影响.实验结果表明,当以2.5%Pd2(dba)3作为催化剂前体,3.75%XantPhos作为配体,吸电子取代和给电子取代的芳基溴代物均可与氨基乙醛缩二乙醇发生C-N交叉偶联反应,高选择性的得到产物N-(2,2-二乙氧基乙基)芳胺,分离收率为73%～96%.

A facile method for the preparation of a broad range of N- （ 2, 2-diethoxyethyl） anilines have been developed from the corresponding aryl bromides and 2-amino acetaldehyde diethyl acetal via modified Buchwald-Hartwig reaction. Pd catalyst in situ generated by Pd2 （dba）3/XantPhos was found to be efficient in this C-N cross-coupling reaction. Under the optimal reaction conditions, both electron-deficient and electron-rich aryl bromides could smoothly convert to their corresponding N-（ 2, 2-diethoxyethyl ）anilines with highly selectivity and the isolated yields were 73% -96%. This new developed method was facile, efficient and easy to operate.