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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]

Visible-light-induced mild, transition metal, base, and photocatalyst-free green protocol has been developed for the synthesis of tryptanthrin and its derivatives. The present reaction is compatible with a wide range of substrates with good to high yields. Further, a novel synthetic transformation of tryptanthrin derivatives has been achieved by the decarboxylative addition of cyanoacetic acid for the first time. This reaction proceeds by visible-light-induced single electron transfer between the substrate and oxygen, followed by intramolecular cyclization without the use of an external photocatalyst. [ABSTRACT FROM AUTHOR]

In this work, we describe the synthesis of a molecule in which fullerene C60 is covalently attached to a bowl-shaped polycyclic aromatic hydrocarbon, corannulene. The developed synthetic route is comprised of four linear steps with isolated yields ranging from 41-91%. The first three steps relate to the preparation of a hydrazone derivative of corannulene carrying a butyric acid methyl ester group. This key compound generates a reactive diazo moiety under base-induced decomposition process. The generated diazoalkane then adds to the C60 molecule to furnish the targeted corannulene-C61-butyric acid methyl ester (CCBM) molecule. This compound is structurally characterized by NMR spectroscopy and mass spectrometry, whereas material properties are determined with the help of optical absorption spectroscopy and cyclic voltammetry. Finally, some preliminary aspects on its application are examined in a poly(3-hexyl thiophene)-based photovoltaic device. [ABSTRACT FROM AUTHOR]

Rieche formylation of corannulene is shown to afford corannulenecarbaldehyde on a multi-gram scale, in a single step, with an isolated yield of 95 %, and without the need of chromatographic purification. This compound allowed facile access to a wide range of corannulene structures. The developed synthetic routes are expected to facilitate the utility of the corannulene motif - known for its unique structural and electronic properties - in the arena of macromolecular and materials chemistry. [ABSTRACT FROM AUTHOR]

A metal-freeone-pot strategy has been developed for the firsttime to synthesize pharmaceutically important α-amino ketonesfrom readily available benzylic secondary alcohols and amines using N-bromosuccinimide. This new reaction proceeds via threeconsecutive steps involving oxidation of alcohols, α-brominationof ketones, and nucleophilic substitution of α-bromo ketonesto give α-amino ketones. Importantly, this novel one-pot greenerreaction avoids direct usage of toxic and corrosive bromine. Thismethodology has been employed efficiently to synthesize pharmaceuticallyimportant amfepramone and pyrovalerone in a single step. [ABSTRACT FROM AUTHOR]

Palladium-catalyzed heteroannulation of N-substituted benzamides with [60]fullerene, which proceeds through direct sp2 C—H bond activation to form 7-membered ring pallada-intermediate with C60, led to formation of [60]fulleroisoquinolinones in moderate to good yields (8-64% based on recovered C60). A plausible reaction pathway is proposed. [ABSTRACT FROM AUTHOR]

A series of isatins (II) is prepared by iodine-catalyzed oxidation-cyclization of o-aminoacetophenones (I) with DMSO as both a reagent and a solvent. [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 .

A novel transition metal-free strategy for the synthesis of benzene-fused β-carboline scaffolds has been developed. This protocol offers a rapid and direct pathway to access the benzene fused β-carboline from 2-(1 H -indol-3-ylsulfanyl)-phenylamines and aryl methyl ketones using an efficient catalytic system of I 2 /DMSO. The present mild protocol proceeds through the sequential reactions of Kornblum oxidation, Pictet-Spengler cyclization, and desulfurization to afford the desired products in excellent yields up to 99%. Moreover, this method has a wide range of substrate tolerance and is operationally simple and applicable in gram-scale synthesis.

A novel molecular I2-catalyzed synthesis of isatins through C(sp(3))-H oxidation and intramolecular C-N bond formation of 2'-aminoacetophenones with excellent yields up to 97% under transition metal, base, additive, peroxide and ligand free conditions is described. The present protocol is suitable for gram scale synthesis of isatins and retained its high yield. Further, the synthetic utility of this present reaction towards synthesis of bioactive 3-hydroxy-2-oxindoles and oxindoles is demonstrated.

Palladium-catalyzed heteroannulation of N-substituted benzamides with [60]fullerene, which proceeds through direct sp(2) C-H bond activation to form 7-membered ring pallada-intermediate with C(60), led to formation of [60]fulleroisoquinolinones in moderate to good yields (8-64% based on recovered C(60)). A plausible reaction pathway is proposed.