Temperature‐Controlled Base‐Promoted Cyclization for the Synthesis of 2‐Amino‐4H‐benzo[d][1,3]thiazin‐4‐ones and 2‐Thioxo‐4(3H)‐quinazolinones

Abstract A base‐promoted and highly selective temperature‐dependent tandem oxidation/decarboxylative cyclization of isothiocyanates and isatins has been developed. This method allows the chemodivergent synthesis of 4 H ‐benzo[ d ][1,3]thiazin‐4‐ones and 2‐thioxo‐2,3‐dihydroquinazolin‐4(1 H )‐ones in moderate to high yields.