Radical relay cyclization/C-C bond formation of allyloxy-tethered aryl iodides with quinoxalin-2(1H)-ones via polysulfide anion photocatalysis.

A visible-light-induced radical relay cyclization/C-C bond formation of quinoxalin-2(1H)-ones with allyloxy-tethered aryl iodides using polysulfide anions as a photocatalyst is described. This protocol allows efficient access to a variety of complicated molecules bearing both quinoxalin-2(1H)-one and 2,3-dihydrobenzofuran motifs in high yields under mild reaction conditions with a broad range of substrates.

Copper-mediated C3-cyanation of indoles by the combination of amine and ammonium.

A copper-promoted C3-cyanation of both the free N-H and N-protected indoles by N,N,N',N'-tetramethyl-ethane-1,2-diamine (TMEDA) and ammonium is achieved. The iminium ion acts as the intermediate in this transformation, which is sequentially electrophilically attacked by indole and H2O followed by hydrolyzation to form the aldehyde. Then the reaction between the aldehyde and ammonium afforded nitriles. The reaction employs O2 as a clean oxidant with good efficiency and functional group tolerance. Thus, it represents a facile and safe procedure leading to 3-cyano indoles.