2-Lithiumthiophene and 2-lithiumpyridine were allowed to react with N-substituted β- aminoesters. Only β-amino arylketones were obtained from N-BOC, NH derivatives, while arylenoates were formed (retro-conjugate addition) from those substrates bearing N-Bn, NH substituents, despite the aryllithium used. When the nitrogen is disubstituted (BOC and Bn), the product distribution depended on the nucleophile, leading to tertiary alcohols for 2- ...