In this communication we describe a new methodology to Dieckmann cyclization of diethyl adipate (1) and diethyl pimelate (3) applying "push-pull" strategy using anhydrous aluminium trichloride and triethylamine in dichloromethane at room temperature. This method is very efficient, simple, safe and reproducible, giving the corresponding cyclic β-keto ester derivatives in 84% and 71% yield, respectively.
Dieckmann cyclization; cyclopentanone derivatives; cyclohexanone derivatives