Electrochemical radical C(sp³)–H arylation of xanthenes with electron-rich arenes

Abstract

C(sp3)-H arylation has recently emerged as a powerful straegy for complex organic molecules synthesis through a new carbon-carbon bond formation. We herein describe an efficient electrochemical C(sp3)-H arylation of xanthenes...

Visible-light-driven photoredox-catalyzed C(sp3)–C(sp3) cross-coupling ofN-arylamines with cycloketone oxime esters

“…1,2 Among them, the alkylation of N -arylamines is one of the most efficient pathways to produce N-containing organic compounds, which introduce a C(sp 3 ) moiety to change the spatial conformation, and increase both the lipophilicity and hydrophilicity as drug candidates. A typical method for the alkylation of N -arylamines mainly relies on CDC (cross-dehydrogenative coupling) reactions; 3 although significant advances have been made along this line, there are still some considerable limitations: (1) most approaches rely heavily on activated alkyl substrates, whose C(sp 3 )–H bonds are adjacent to the heteroatom (such as O, S and N) or the electron-withdrawing group (such as a nitrile, an ester, a ketone and an amide) and (2) super-stoichiometric oxidants and high temperatures are usually required, leading to poor chemoselectivity and atom economy. Therefore, the development of mild and sustainable synthetic strategies to accomplish challenging C(sp 3 )–C(sp 3 ) cross-coupling through α-amino C–H functionalization is still highly desirable.…”

Electrochemical Oxidative C–C Bond Cleavage of Ketones for C–N Bond Formation: A Route to Amides

“…Recently, electrochemical synthesis has attracted increasing attention because it avoids the use of catalysts and oxidants and thus meets the requirements of green and sustainable chemistry. − Electrochemical carbon–carbon bond activation has been regarded as a continuous and scalable method that employs electricity to replace byproduct-generating chemical reagents. This general strategy allows for the development of bond-forming reactions that are often elusive .…”

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 .…”