Isatoic anhydrides, uses in heterocyclic

Indolizine chemistry, advances in, 23, 103 Indolones, isalogens and. 22, 123 lndoxazenes. 8, 277 29, 1 Isatin, chemistry of, 18, I Isalogens and indolones, 22, 123 Isatoic anhydrides, uses in heterocyclic synthesis, 28, 127... 

Isatoic Anhydrides and Their Uses in Heterocyclic Synthesis T. Kappe and W. Stadlbauer, Adv. Heterocycl. Chem., 1981, 28, 127-182. 

Isatoic Anhydrides and Their Uses in Heterocyclic Synthesis... 

There are two important general types of reaction by which six-membered heterocycles containing two or more heteroatoms can be transformed into other six-membered heterocyclic systems, namely reactions which involve an ANRORC mechanism, and reactions which proceed by a Diels-Alder/retro-Diels-Alder type of mechanism. Transformation of 1,3-oxazinones and -thiazinones into pyrimidones (equations 193 and 194) has been extensively used, especially in the conversion of isatoic anhydride into quinazolinones (e.g. equation 195). 2,4-Diaryl-l,2,3,5-oxathiadiazines, which are readily accessible by reaction of sulfur trioxide with aryl isocyanates, are useful precursors to pyrimidines and 1,3,5-triazines (equation 196). 

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