Table . Substrate scope with respect to the cyclic β-dicarbonyl derivatives a a Unless noted otherwise, the reactions were performed using cyclic β-dicarbonyl (0.2 mmol), 2b (0.3 mmol) and NaH (0.3 mmol) in THF (2 mL) at 60 °C. See Supporting Information for detailed procedures. b Ran on a 5 mmol scale.