Benzotriazole stabilized lithium intermediates as a route to the elaboration of N-substituents in amides

Abstract

Lithiation of N-(benzotriazol-1-ylmethyl)benzamide or N-(benzotriazol-1-ylmethyl)-2,2-dimethylbutyramide, readily prepared from the corresponding amides, formaldehyde and benzotriazole, followed by quenching with various electrophiles, such as alkyl halides, ketones or ester, gives the corresponding N-substituted derivatives. Subsequent displacement of the benzotriazole group with Grignard reagents, thiols or alcohols provides access to a wide variety of N-substituted amides in good yields. Treatment of the N-(benzotriazol-1-ylalkyl)benzamides with n- BuLi afforded the 1,1-dibenzamidoalkanes.