Mn(OAc) 3 *2H 2 O promoted addition of arylboronic acids to quinoxalin-2-ones

Mn(OAc)3 Induced C-4 Arylations of Quinazoline 3-Oxides with Arylboronic Acids

“…The elemental composition of the newly prepared 2 was determined by HRMS analysis. Mn(III) induced carbon-boron bond homolysis provides phenyl radical 21 which attacks the C-4 position of quinazoline 3-oxide 1 is producing intermediate A. One more electron transfer from A to Mn(III) could provide B, and its deprotonation facilitated by the acetate anion gives rise to 2 (Scheme 1).…”

“…It was used to synthesise 3-aryl quinoxalin-2-one derivatives through an oxidative cross-coupling of arylboronic acids with quinoxalin-2ones. 21 Diaryl 1,2-diketones were synthesized directly from arylboronic acids and arylpropiolic acids by using Mn(III) acetate via radical pathway in moderate to good yields. 22 In an earlier study, we have reported the synthesis of quinazoline 1-ols and their ring expansion upon carbamoylation with aryl isocyanates.…”

Recent Advances on the Catalytic Functionalization of Quinoxalin- 2(1H)-ones via C-H Bond Activation

“…[40] In 2018, Reddy and coworkers developed a simple and efficient method for the synthesis of 3-arylquinoxalin-2(1H)-one derivatives through an oxidative cross-coupling of arylboronic acids with quinoxalin-2(1H)-ones using a readily available oxidant Mn(III) acetate dehydrate (Scheme 18). [41] This method provided 3-arylquinoxalin-2(1H)-ones scaffolds with a broad substrate scope. However, the reaction required higher temperature, which would limit their application in organic synthesis.…”

Metal Free Benzylation and Alkylation of Quinoxalin‐2(1H)‐ones with Alkenes Triggered by Sulfonyl Radical Generated from Sulfinic Acids

“…Consequently, several reports have been documented to synthesize C3‐substituted quinoxalin‐2(1 H )‐ones . While much development has been made with respect to arylation,– acylation,– amination,– phosphonylation– directly at the C3 position using easily available quinoxalin‐2(1 H )‐ones, functionalization by benzyl, alkyl and fluoroalkyl groups are less explored, despite the importance and predominance of this scaffold as pharmaceuticals that include MDR antagonist, aldose reductase inhibitor, MAO‐A inhibitor, ion channel blocker, antitumor, anti‐inflamatory, and antiobesity agents (Figure ) . Very recently, C3 position of quinoxalin‐2(1 H )‐one has been directly benzylated and alkylated using methylarenes and ethers, respectively (Scheme a).…”