Ruthenium Complex-Controlled Catalytic <i>N</i>-Mono- or <i>N,N</i>-Dialkylation of Heteroaromatic Amines with Alcohols
作者:Yoshihisa Watanabe、Yasuhiro Morisaki、Teruyuki Kondo、Take-aki Mitsudo
DOI:10.1021/jo9516289
日期:1996.1.1
Heteroaromatic amines were N-alkylated with primary alcohols at 150-200 degrees C in the presence of a catalytic amount of various ruthenium complexes to give the corresponding monoalkylated and dialkylated amines in good to high yields. For example, 2-aminopyridine reacted with an excess of ethanol at 180 degrees C for 20 h in the presence of dichlorotris(triphenylphosphine)ruthenium [RuCl(2)(PPh(3))(3)]
在催化量的各种钌络合物的存在下,在150-200℃下用伯醇对杂芳族胺进行N-烷基化,从而以良好或高收率得到相应的单烷基化和二烷基化胺。例如,在二氯三(三苯基膦)钌[RuCl(2)(PPh(3))(3)]存在下,2-氨基吡啶与过量的乙醇在180摄氏度下反应20小时,得到2-(乙基氨基)吡啶(1)和2-(二乙氨基)吡啶(2)的产率分别为9%和70%。另一方面,即使将(eta(4)-1,5-环辛二烯)(eta(6)-1,3,5-环辛三烯)钌[Ru(cod)(cot)]用作催化剂,在存在过量乙醇的情况下,以85%的高收率获得了1。向Ru(cod)(cot)中添加叔膦和亚磷酸酯可提高二烷基化胺的收率。