One-pot synthesis of 2-ferrocenyl-substituted pyridines

A facile, one-pot method for the synthesis of 2-ferrocenylpyridines is described. When reacted with propargylamine, alpha,beta-alkynic ketones produced N-propargylic beta-enaminones in situ, which, in the presence of copper(I) chloride, underwent electrophilic cyclization to afford 2-ferrocenylpyridine derivatives in good to high yields. This cyclization was found to be general for a variety of alpha,beta-alkynic ketones and tolerated the presence of aryl groups with electron-withdrawing and electron-donating substituents. The enrichment of the pyridine core with a ferrocenyl moiety, in addition to benzoyl groups, may offer potential for the synthesis of molecules of pharmacological interest. (C) 2016 Elsevier Ltd. All rights reserved.