Synthesis of New 5-Chloroisatin Derivatives

We prepared new 5-chloroisatin derivatives via alkylation reactions under liquid-solid phase transfer catalysis conditions using various alkylating agents. In all cases, we were able to isolate a single type of N-alkyl compound in good yields. Subsequently, we developed the synthesis of five-membered heterocycles through 1,3-dipolar cycloaddition reactions on the dipolarophilic groups of 5-chloroisatin (the carbonyl group at position 3 and the allyl chain at position 1).