AnionicN-Fries Rearrangement ofN-Carbamoyl Diarylamines to Anthranilamides. Methodology and Application to Acridone and Pyranoacridone Alkaloids

[reaction: see text] A general alkyllithium/LDA-mediated rearrangement of N-carbamoyl diarylamines 7a-g into the anthranilamides 8a-g and 9a-g (Table 1) is presented and applied to a regioselective efficient construction of acridone (17) and pyranoacridone (18) alkaloids (Scheme 4).