Staudinger Cleavages of Amides on Naphthalene for the Ipsilateral Effect of 1,8-Substituents.

8-(Azidomethyl)-1-naphthoic acid was elaborately prepared, and its coupling with amines provided the corresponding 8-(azidomethyl)-1-naphthamides. The Staudinger reactions of 8-(azidomethyl)-1-naphthamides with phosphine produced iminophosphoranes, and easy intramolecular cyclization of the iminophosphoranes afforded 2,3-dihydro-1-benzo[]isoquinolin-1-one leaving amines with almost quantitative conversion rates for the ipsilateral effect of 1,8-substituents on naphthalene. The protocol exhibits some advantages, including a readily available protecting group, cleavages of amides in almost quantitative conversion rates, an aqueous medium, reactions at room temperature, a broad substrate scope, wide functional group tolerance, and suitable scale-up reactions.

Visible-Light-Mediated Aerobic Oxidation of N-Alkylpyridinium Salts under Organic Photocatalysis.

Quinolones and isoquinolones exhibit diverse biological and pharmaceutical activities, and their synthesis is highly desirable under mild conditions. Here, a highly efficient and environmentally friendly visible light-mediated aerobic oxidation of readily available N-alkylpyridinium salts has been developed with Eosin Y as the organic photocatalyst and air as the terminal oxidant, and the reaction provided quinolones and isoquinolones in good yields. The method shows numerous advantages including mild and environmentally friendly conditions, high efficiency, tolerance of wide functional groups and low cost.