Room temperature cyclization of arylpropiolic acid anhydride: Synthesis of naphtho[2,3-c]furan-1,3-dione derivatives

Cyclic anhydrides such as naphtho2,3-c]furan-1,3-dione derivatives were synthesized from the reaction of arylpropiolic acids and 2-chloro-4,6-dimethoxy-1,3,5-triazine in the presence of N-methylmorpholine at room temperature. This mild condition provided the naphtho2,3-c]furan-1,3-dione derivatives in good yields. Spectroscopic analysis suggested that the formation of arylpropiolate is the rate-determining step.