Synthesis of β-amino arylketones through the addition of ArLi derivatives to β-aminoesters

2-Lithiumthiophene and 2-lithiumpyridine were allowed to react with N-substituted β-aminoesters. Only β-amino arylketones were obtained from N-BOC, N-H derivatives, while arylenoates were formed (retro-conjugate addition) from those substrates bearing N-Bn, N-H 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-lithiumthiophene or ketones for 2-lithiumpyridine. Tertiary alcohols were also formed when PhLi was used as a nucleophile.