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An iodine/DMSO‐promoted approach has been developed for the synthesis of indoloquinolines via a sequential sp3 C−H oxidation/intramolecular cyclization using 2‐(1H‐indol‐2‐yl)anilines and aryl methyl ketones. A wide range of aryl methyl ketones, including drugs and complex bioactive molecule‐derived substrates were compatible in the present reaction with yields in the range of 30–96%. This protocol proceeds through sp3 C−H oxidation of aryl methyl ketones to phenylglyoxals, subsequent imine formation, and cyclization to furnish the indoloquinolines. Further, the reaction is applicable for gram‐scale synthesis and is operationally simple. [ABSTRACT FROM AUTHOR]

A metal-free, iodine-catalyzed protocol has been developed for constructing biologically significant 5-aroyl 1,2,4-oxadiazole scaffolds using aryl methyl ketones and amidoximes. The strategy produces structurally diverse 5-aroyl 1,2,4-oxadiazoles in good to excellent yields, with a broad substrate scope that includes drug derived substrates. The reaction proceeds through iodine/DMSO-mediated oxidation of aryl methyl ketones, followed by imine formation and subsequent cyclization to yield the desired products. Additionally, this protocol has successfully produced the carbonyl analogs of ataluren and tioxazafen and has facilitated some intriguing late-stage transformations.

An I 2 -promoted, metal-free protocol has been developed for the one-pot synthesis of 6-aroyl-5,6-dihydro-8 H -quinazolino[4,3- b ]quinazolin-8-ones from readily accessible substrates. This reaction involves the in situ sp 3 C-H oxidation of aryl methyl ketones to phenylglyoxal, followed by imine formation and intramolecular nucleophilic addition, resulting in the formation of two new C-N bonds. Furthermore, the method is applicable to a wide range of aryl methyl ketones, including heterocycles and drug-derived substrates, yielding the desired products with yields ranging from 62% to 93%. Additionally, the practical utility of this approach was demonstrated through gram-scale synthesis.

An efficient, transition-metal-free protocol employing I 2 /Cs 2 CO 3 for the synthesis of thiosulfonate containing 2-iminoindolin-3-ones motifs has been developed from C-3 phenylthio indoles. The reaction proceeded through intramolecular cyclization involving C-N bond formation, leading to the formation of indole-fused benzothiazines as a key intermediate. Remarkably, Cs 2 CO 3 played a crucial role in the reaction as an oxygen source, enabling oxidative rearrangement with [1,4]-sulfonyl migration to furnish the final products with the formation of multiple functional groups such as C═O, C═N, and S-SO 2 .