Visible-light-promoted cascade radical cyclization for the synthesis of sulfonylated benzimidazo/indolo[2,1- a ]iso-quinolin-6(5 H )-ones has been reported. The reaction provides transition-metal-free and expeditious access to sulfonylated polyaromatics. The use of sodium metabisulfite as a SO 2 surrogate and the rapid generation of molecular complexity using a three-component photochemical protocol are the salient features of this reaction manifold.

We report a photocatalytic approach for the installation of the amide moiety onto para-quinone methides. This transformation features a net reductive approach for the generation of carbamoyl radicals from amidesubstituted Hantzsch ester derivatives under transition metal-free conditions. This protocol exhibits wide scope and allows access to diarylacetamides employing a C−C bond formation approach.

The development of excited-state palladium-catalyzed alkylative cyclization of acrylamides and the alkylation of quinoxalinones is described. The application of a variety of primary, secondary, and tertiary unactivated alkyl halides as alkyl radical precursors and the use of a simple catalyst system are the highlights of this reactivity manifold. The reactions exhibit wide scope, occur under mild conditions, and furnish the products in excellent yields.

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We report on a visible light-mediated cascade carbamoylation/cyclization of acrylamides using dihydropyridyl carbamoyl donors derived from alkyl amines. Diversely selected acrylamides including 2-cyano-N-arylacrylamides, indolyl-and benzimidazolyl acrylamides, and 2-alkynyl-N-aryl acrylamides participate in this reaction, providing products in good yields. The highlights of this photochemical method include the application of alkyl amine-derived carbamoyl donors, peroxide-free reaction conditions, and a broad scope.