Transition-metal-catalyzedorthoC–H functionalization of 2-arylquinoxalines

Abstract

Recently, direct C−H bond activation and functionalization has become a prodigious and hot topic among the synthetic organic chemists due to its step-economic nature and substantial synthetic versatility. On the...

Recent advances in spirocyclization of maleimides via transition-metal catalyzed C–H activation

“…The 2-arylquinoxaline scaffold has received a great deal of attention in recent years as a potential DG for C-H activation. 32 In 2021, a Ru-catalyzed quinoxaline directed spirocyclization approach was reported by Laru et al 33 employing AgSbF 6 (20 mol%), Cu(OAc) 2 •H 2 O (1.0 equiv.) and AcOH (2.0 equiv.)…”

Visible-light-induced cascade reaction: a sustainable approach towards molecular complexity

“…Among the nitrogen-containing heterocycles, quinoxalines are widely studied in chemical synthetic literature. 37 Xu et al 38 in April 2019 introduced a methodology for the synthesis of the indolo[2,1- a ]isoquinoline core structure via a radical cascade reaction driven by visible light. As per the reported methodology, the authors employed 2-aryl indoles ( 18a , 0.2 mmol), aroyl chloride ( 18b , 0.4 mmol) along with fac -Ir(ppy) 3 (1 mol%) as an active catalyst, 2,4,6-collidine as a base, CH 3 CN as a solvent under the irradiation of blue LEDs at 25 °C in an N 2 atmosphere.…”

Visible light-induced organophotoredox-catalyzed difunctionalization of alkenes and alkynes

“…In recent years, the study of quinoxaline and its derivatives has gained interest due to their diverse range of biological activities and therapeutic applications. 47 In 2021, Yue, He, and co-werkers 48 disclosed a method for the difunctionalization of alkenes via the four-component tandem reaction of quinoxalin-2(1 H )-ones ( 31b ), alkenes ( 31a ), aryldiazonium ( 31c ), and sodium metabisulfite ( 31d ) under visible-light irradiation and metal-free conditions. This method efficiently formed C–S and C–C bonds across a double bond simultaneously.…”