Synthesis 2004(2): 208-212  
DOI: 10.1055/s-2003-44383
PAPER
© Georg Thieme Verlag Stuttgart · New York

Organic Reactions in Ionic liquids: N-Alkylation of Phthalimide and Several Nitrogen Heterocycles

Zhang-Gao Lea,b,c, Zhen-Chu Chen*a,b, Yi Hub, Qin-Guo Zhengd
a Ningbo Institute of Technology, Zhejiang University, Ningbo, 315100, P. R. China
b Department of Chemistry, Zhejiang University (xi xi campus), Hangzhou, 310028, P. R. China
e-Mail: zhenchuc@mail.hz.zj.cn;
c Department of Applied Chemistry, East China Institute of Technology, Fuzhou, 344000, P. R. China
d Pharmaceutical Science Reseach Institute, Aston University, Aston Triangle, Birmingham B4 TET, UK
Further Information

Publication History

Received 28 July 2003
Publication Date:
15 December 2003 (online)

Abstract

N-Alkylation of heterocyclic compounds bearing an acidic hydrogen atom attached to nitrogen with alkyl halides is accomplished in ionic liquids ([bmim]BF4 = 1-butyl-3-methylimidazolium tetrafluoroborate, [bmim]PF6 = 1-butyl-3-methylimida-zolium hexafluorophosphate, [buPy]BF4 = butylpyridinium tetra­fluoroborate) in the presence of potassium hydroxide as a base. In this manner, phthalimide, indole, benzimidazole, succinimide can be successfully alkylated. The procedure is convenient, efficient, and generally affords the N-alkylated product exclusively.