A catalyst-free, facile and efficient approach to cyclic esters: synthesis of 4H-benzo[d][1,3]dioxin-4-ones

A metal and additive free base-mediated method for the formation of 4H-benzo[d][1,3]dioxin-4-one and its derivatives, from salicylic acids and dichloromethane, was developed using dichloromethane (DCM) and 1,1-dichloroethane (1,1-DCE) as the C1 source.