Superelectrophiles in Synthesis: Preparation of Aromatic Imides

Aromatic carboxylic acids are found to undergo reactions with isocyanates, wherein triflic acid promotes the formation of aromatic imide products in fair to good yields. It is proposed that the carboxylic acid group directs the isocyanate electrophile to the ortho -position. This is thought to occur by the formation of a temporary carbamic acid anhydride group, which cleaves upon ortho -functionalization. A series of imide products are synthesized, and the synthesis of a potential selective inhibitor of tyrosyl DNA phosphodiesterase II is performed.