Persulfate-nitrogen doped graphene mixture as an oxidant for the synthesis of 3-nitro-4-aryl-2-chromen-2-ones from aryl alkynoate esters and nitrite.

A series of 3-nitro-4-aryl-2-chromen-2-ones in good yields have directly been obtained from aryl alkynoate esters and nitrite by employing a mixture of KSO-nitrogen doped graphene as an oxidant in a watery medium at room temperature. A plausible mechanism for the reaction is also reported. It reveals that the product is formed through a cascade of nitro radical addition, spirocyclization, and ester migration.

Persulfate-activated charcoal mixture: an efficient oxidant for the synthesis of sulfonated benzo[][1,3]oxazines from -(2-vinylphenyl)amides and thiols in aqueous solution.

A series of 2,4-aryl-4-((arylsulfonyl)methyl)-4-benzo[][1,3]oxazines in good to excellent yields have directly been obtained from -(2-vinylphenyl)amides and thiols by employing a mixture of KSO-activated charcoal in aqueous acetonitrile solution at 50 °C. A plausible mechanism for the reaction is reported. It reveals that the reaction follows a radical pathway and the persulfate has been the oxygen source for formation of the sulfone group in the products.