2-Alkyl imidazoles can be considered as tridentate nucleophiles that can give four consecutive attacks on electrophiles which ultimately generate highly functionalized heterocyclic ring systems. Previously it had been shown that these secondary enamine type molecules readily react with different 1,3-diacid chlorides and form polycyclic acyl substituted N, N'-Ketene acetals. Recently we demonstrated that when 2-ethyl imidazoles were reacted with different 1,3 diacid chloride then a series of novel pyrrollo-[1, 2-c]imidazole diones were formed from intermediate N,N'-cyclic ketene acetals. Triethylamine was used as base and reactions were performed in refluxing acetonitrile. Further, reactions of 2-isopropyl imidazoles with similar 1,3 diacid chlorides exclusively gave pyrrollo-[1, 2-c]imidazole diones. These new systems can be viewed as bidentate nucleophiles.Therefore reactions with different electrophiles can lead to different product channels and more than one nucleophile can be employed in each reaction sequence.
Heterocycles and Aromatics
1:00 PM-5:20 PM, Monday, August 17, 2009 Walter E. Washington Convention Center -- 206, Oral