Ambient Temperature Cleavages of Amides in an Aqueous Medium for the Ipsilateral Effect of 1,8-Substituents on Naphthalene.

The selective release of a molecule in its native form from a constructed framework is very attractive in the chemical and biological fields. The amide bond is ubiquitous in biological and chemical systems. However, the cleavage of an unmodified typical amide is a great challenge because of its high level of stabilization. Here, couplings of 8-azido-1-naphthoic acid prepared by us with amines afforded 8-azido-1-naphthamides. Reductions of 8-azido in 8-azido-1-naphthamides with sodium sulfide yielded 8-amino-1-naphthamides, and then, fast intramolecular nucleophilic attack of 8-amino to carbonyl of 1-amido in the presence of silica gel as the additive afforded 2,3-benzo[cd]indol-2(1H)-one freeing amines in almost quantitative conversion rates for the ipsilateral effect of 1,8-substituents on naphthalene. Furthermore, this strategy was extended to the cleavages of esters (alkyl 8-azido-1-naphthoates) successfully. The cleavages of amides and esters were performed in an aqueous medium at room temperature with wide functional group tolerance and were suitable for gram-scale production.