Electro-oxidative cyclization: access to quinazolinones via K2S2O8 without transition metal catalyst and base

A K2S2O8-promoted oxidative tandem cyclization of primary alcohols with 2-aminobenzamides to synthesize quinazolinones was successfully achieved under undivided electrolytic conditions without a transition metal and base. The key feature of this protocol is the utilization of K2S2O8 as an inexpensive and easy-to-handle radical surrogate that can effectively promote the reaction via a simple procedure, leading to the formation of nitrogen heterocycles via direct oxidative cyclization at room temperature in a one-pot procedure under constant current. Owing to the use of continuous-flow electrochemical setups, this green, mild and practical electrosynthesis features high efficiency and excellent functional group tolerance and is easy to scale up.

Automated summary

The oxidative tandem cyclization of primary alcohols with 2-aminobenzamides to synthesize quinazolinones using K2S2O8 as a radical surrogate under undivided electrolytic conditions is a green, mild, and practical method with high efficiency and excellent functional group tolerance. The use of continuous-flow electrochemical setups allows for easy scalability of the reaction.