Oxidative Ring Opening of 1,3‐Diarylbenzo[c]heterocycles Using m‐CPBA: Preparation of 1,2‐Diaroylbenzenes

Abstract

An unprecedented oxidative cleavage of benzo[c]heterocycles using m‐CPBA is reported. The reaction of 1,3‐diaryl benzo[c]heterocycles with m‐CPBA (meta‐chloroperoxybenzoic acid) at room temperature for 5 min led to the formation of 1,2‐diaroylbenzenes in good to excellent yields.

Ring Opening of π-Delocalized 2,5-Diphenyltellurophene by Chemical or Self-Sensitized Aerobic Photooxidation

“…This oxidative ring-opening reaction by m CPBA has in fact been previously reported for other five-membered heterocycles, including furans and selenophenes, , leading to the ene-diones as the major product. This has also been shown for aryl-substituted benzo­[ c ]­thiophenes, yielding diaroylbenzenes as the ring-opened products . The lack of soluble products or byproducts containing Te suggests that Te is removed from solution as the observed white precipitate.…”

“…This has also been shown for aryl-substituted benzo[c]thiophenes, yielding diaroylbenzenes as the ring-opened products. 51 The lack of soluble products or byproducts containing Te suggests that Te is removed from solution as the observed white precipitate. It can be concluded that the tellurium was not extruded as Te(0), which is gray.…”

Oxidative cleavage of 1,3-diaryl/(heteroaryl)benzo[c]furans into 1,2-diaroyl/(heteroaroyl)benzenes using selenium dioxide

“…The oxidative cleavage of benzo[c]furan 1a (0.23 g, 0.85 mmol) using SeO 2 (0.15 g, 1.35 mmol) adopting the general procedure gave known diketone 2a 9 …”

Diels–Alder Reaction of 1,3-Diarylbenzo[c]furans with Thiophene S,S-Dioxide/Indenone Derivatives: A Facile Preparation of Substituted Dibenzothiophene S,S-Dioxides and Fluorenones

“…Our aim is to explore the synthetic utility of 1,3-disubstituted benzo[ c ]furans as a diene in the Diels–Alder reaction to prepare π-conjugated dibenzothiophene S , S -dioxide and fluorenone derivatives. Recently, Iniesta and co-workers achieved the preparation of dibenzothiophene S , S -dioxides through Diels–Alder reaction of benzo[ b ]thiophene S , S -dioxide and tetraphenylthiophene S- oxide.…”