Studies on the Synthesis of the Sydnone Derivatives and its Properties IV: The Diarylation of Sydnone Compound

Abstract In the presence of H2SO4, the sydnone rings were condensed with formaldehyde to give diarylation in 4‐position of the sydnone rings: 3,3′‐diphenyl‐4,4′‐methylenedisydnone is obtained from 3‐phenylsydnone in 61% yield, and 3,3′‐di‐p‐methylphenyl‐4, 4′‐methylenedisydnone is obtained from 3‐(4′‐methylphenyl)sydnone in 70% yield. And the possible reaction mechanism is discussed.