In 2022,Agafonova, Anastasiya V.; Sakharov, Pavel A.; Smetanin, Ilia A.; Rostovskii, Nikolai V.; Khlebnikov, Alexander F.; Novikov, Mikhail S. published an article in Organic Chemistry Frontiers. The title of the article was 《Stannyl radical-mediated synthesis of 6H-1,3-oxazin-6-ones from 2-acyloxyazirines or whether free radicals can open the azirine ring》.Reference of 4-Iodobenzoic acid The author mentioned the following in the article:
A fundamentally new radical cascade reaction of 2-acyloxyazirines provides an effective one-step method for the preparation of 5-hydroxy-6H-1,3-oxazin-6-ones from Me 2-acyloxy-2H-azirine-2-carboxylates using a Bu3SnH/ACHN system as a source of stannyl radicals. The method provides high product yields from a variety of 2-aroyloxy-, 2-hetaroyloxy-, and 2-tert-alkylcarbonyloxy-substituted Me azirine-2-carboxylates. The decreasing volume of the acyloxy substituent causes a side reaction leading to the formation of Me oxazole-2-carboxylates. According to the DFT calculations, the switch between these reaction pathways occurs when changing the C1-substituent in the 2-azabuta-1,3-dien-4-oxyl intermediate, the volume of which controls further stabilization routes: radical-radical recombination or Z,E isomerization followed by recombination. The hydroxyl group in 5-hydroxy-6H-1,3-oxazin-6-ones can be easily replaced, through a triflation step, with aryl, pyridyl, alkenyl, alkynyl, and cyano groups by palladium-catalyzed cross-coupling reactions. 5-Hydroxy-6H-1,3-oxazin-6-ones were converted to pyridine-2,3(1H,4H)-diones in good yields via copper-catalyzed transannulation with 3-tolyl-2H-azirine. The key step of this new domino reaction is the copper-catalyzed pyrrolooxazine-oxazolopyridine isomerization, which, according to the DFT calculations, proceeds via a concerted mechanism. In addition to this study using 4-Iodobenzoic acid, there are many other studies that have used 4-Iodobenzoic acid(cas: 619-58-9Reference of 4-Iodobenzoic acid) was used in this study.
4-Iodobenzoic acid(cas: 619-58-9) belongs to organic iodides. Generally organic iodides can be divided into two classes of alkyl iodides and aryl iodides. Typical reactions of alkyl iodides include nucleophilic substitution, elimination, reduction, and the formation of organometallics.Reference of 4-Iodobenzoic acidHalogenation of aromatic hydrocarbons is a very important reaction via an electrophilic aromatic substitution.
Referemce:
Iodide – Wikipedia,
Iodide – an overview | ScienceDirect Topics – ScienceDirect.com