Practical synthesis of 3-aryl anthranils via an electrophilic aromatic substitution strategy

Abstract

We report a practical route for the synthesis of valuable 3-aryl anthranils from readily available anthranils and simple arenes by using the classical electrophilic aromatic substitution (EAS) strategy. This transformation...

Electrochemical Site-Selective Alkylation of Azobenzenes with (Thio)Xanthenes

“…Based on the above mechanistic experiments and previous reports [ 41 , 42 , 43 , 45 , 46 , 47 , 48 , 49 ], a possible reaction mechanism is proposed in Scheme 6 . Firstly, anodic oxidation of xanthene 2a led to the formation of intermediate I , which was further deprotonated to generate radical II , followed by an anode oxidation to form the cationic species III .…”

Condensed Osmaquinolines with NIR‐II Absorption Synthesized by Aryl C−H Annulation and Aromatization

“…[13] Anthranil is a significant aromatic heterocycle and can serve as a building block that potentially could extend π-conjugation. [14] Anthranil derivatives with diverse substituents are readily accessible, [15] thus it is feasible to install various groups in anthranils to modulate the strength of the charge transfer. These characteristics have encouraged us to explore the reaction of anthranils with metallaaromatics with the aim of discovering new πextended aza-metallaaromatics with broad absorptions.…”

Tf2O-Promoted Chemoselective C3 Functionalization of Anthranils with Phenols and Thiophenols

“…The investigation commenced with anthranil 1a and thiophenol 2a as model substrates. Following our previous work, the initial attempt was performed with 1a (0.20 mmol) and 2a (0.24 mmol) using Tf 2 O (0.20 mmol) as a promoter in DCE (Table , entry 1). However, only a trace amount of 3-(phenylthio)­benzo­[ c ]­isoxazole ( 4a ) was detected, and the main product was 1,3-adduct 3a .…”

“…The residue was extracted with D 2 O and analyzed by 19 F NMR. The peak at −87.4 ppm was assigned to CF 3 SO 2 – , indicating that a CF 3 SO 2 H is eliminated from 3a in aromatization. , Although the details of the elimination process are still ambiguous, this protocol provides an expedient method for the synthesis of 3-thio anthranils. Tf 2 O plays a critical role in this transformation.…”

“…Soulé and Doucet reported a palladium-catalyzed C3 arylation of anthranils with aryl iodide, and Hashmi et al disclosed a photoinduced method to access 3-aryl anthranils from aryl diazonium tetrafluoroborates . Recently, our group achieved a trifluoromethanesulfonic anhydride (Tf 2 O) promoted formal oxidative coupling of anthranils and electron-rich arenes for the practical synthesis of 3-aryl anthranils via an electrophilic aromatic substitution (EAS) strategy . In this novel protocol, simple anthranils are first activated by Tf 2 O to generate active cation species A or analogues, which then undergo a Friedel–Crafts type reaction with electron-rich arenes to afford the desired 3-aryl anthranils after rearomatization.…”