01413nas a2200169 4500008004100000022001400041245015600055210006900211260000800280300001200288490000700300520073800307100002701045700002401072700002601096856012101122 2018 eng d a1477-052000aEosin Y photoredox catalyzed net redox neutral reaction for regiospecific annulation to 3-sulfonylindoles via anion oxidation of sodium sulfinate salts0 aEosin Y photoredox catalyzed net redox neutral reaction for regi cJAN a536-5400 v163 a
An eosin Y photoredox catalyzed net redox neutral process for 3-sulfonylindoles via the anionic oxidation of sodium sulfinate salts and its radical cascade cyclization with 2-alkynyl-azidoarenes was developed with visible light as a mediator. The reaction offers metal and oxidant/reductant free, visible light mediated vicinal sulfonamination of alkynes to 2-aryl/alkyl-3-sulfonylindoles and proceeds via the generation of a sulfur-centered radical through direct oxidation of the sulfinate anion by an excited photocatalyst with a reductive quenching cycle. The mild conditions, use of an organic dye as photo-catalyst, bench stability and easily accessible starting materials make the present approach green and attractive.
1 aRohokale, Rajendra, S.1 aTambe, Shrikant, D.1 aKshirsagar, Umesh, A. uhttp://library.ncl.res.in/content/eosin-y-photoredox-catalyzed-net-redox-neutral-reaction-regiospecific-annulation-3