ZrCl4 as an efficient catalyst for one-pot synthesis of highly functionalized piperidines via multi-component organic reactions

摘要

A highly atom-economic, one-pot synthesis of functionalized piperidines is reported by a multi-component condensation reaction between beta-keto ester, two equivalents of aromatic aldehyde, and two equivalents of amine in the presence of a catalytic amount of ZrCl4. The advantages of this protocol are good yields, short reaction time, mild reaction conditions, no need for column chromatography, more readily available, inexpensive catalyst, and simple work-up procedure.