Identify the major product of the following reaction:

Step-by-step solution

The reaction proceeds via a tandem alkylation-cyclization sequence. First, the strong base NaOEt abstracts the highly acidic proton from the - CH ₂- group located between the electron-withdrawing pyridine ring and the ester group, forming a resonance-stabilized carbanion. The reagent 2-(2-bromoethyl)oxirane has two electrophilic sites: a primary alkyl bromide and an epoxide. The soft carbanion preferentially attacks the less sterically hindered and softer primary bromide via an S _ N 2 mechanism, displacing the bro