Synthesis of Isatins by I₂/TBHP Mediated Oxidation of Indoles

Abstract

An I2/TBHP mediated oxidation of commercially available indoles has been developed, which affords isatins in moderate to good yields.

TBHP Mediated Substrate Controlled Oxidative Dearomatization of Indoles to C2/C3‐Quaternary Indolinones

“…Unlike C3‐oxygenation, C2‐oxygenation of N ‐methylindole is quite intriguing. It was previously reported in the literature that TBHP/I 2 reagent system facilitated the C2‐oxygenation of (NMe)‐indoles through 3‐iodo iminium intermediate which eventually yielded isatin as the final product . However, during our investigation with TBHP in the absence of I 2 , the formation of C3‐quaternary indolinone 3a was observed instead of isatin derivative.…”

Titania‐Supported Gold Nanoparticles as Efficient Catalysts for the Oxidation of Cellobiose to Organic Acids in Aqueous Medium

“…In 2011, Wan and co‐workers reported the synthesis of N ‐methylisatin through a ruthenium‐catalyzed oxidative procedure 15. Recently, Ji et al demonstrated the versatile synthesis of isatins through I 2 / tert ‐butyl hydroperoxide (TBHP)‐mediated direct oxidation of indoles 16. Very recently, Kirsch and co‐workers described the direct conversion of indoles into isatins in the presence of 2‐iodoxybenzoic acid (IBX)–SO 3 K/NaI 17.…”

Copper‐Catalyzed Radical Sulfonylation of N‐Propargylindoles with Concomitant 1,2‐Aryl Migration

“…Additionally, when the reaction was performed in presence of H 2 18 O (13 μ L), the 18 O labeling products were obtained ( 3 a ‐ 16 O/ 3 a ‐ 18 O=73:27). The 18 O‐labeled experiment demonstrated that the oxygen atom of product came from TBHP or water in the TBHP aqueous solution and Cu(NO 3 ) 2 ⋅ 3H 2 O (see the Supporting Information) …”

“…The plausible mechanism has been proposed in Scheme on the basis of the control experiments and literature precedence ,. Initially, the reaction of sulfonyl hydrazides with tert ‐butylperoxy ( t ‐BuOO . )…”