Structure-based virtual screening is an important tool in early stage drug discovery that scores the interactions between a target protein and candidate ligands. As virtual libraries continue to grow (in...

Here we report a catalytic method for the intermolecular anti-Markovnikov hydroamination of unactivated alkenes using primary and secondary sulfonamides. These reactions occur at room temperature under visible light irradiation and are jointly catalyzed by an iridium(III) photocatalyst, a dialkyl phosphate base, and a thiol hydrogen atom donor. Reaction outcomes are consistent with the intermediacy of an N-centered sulfonamidyl radical generated via proton-coupled electron transfer activation of the sulfonamide N-H bond. Studies outlining the synthetic scope (>60 examples) and mechanistic features of the reaction are presented.

The Linguistic Data Consortium (LDC) is currently involved in a major effort to expand its multilingual text resources, in particular for machine translation, message understanding and information retrieval research. The main sources for data acquisition are governmental and international organizations, newswire services, and diverse publishers. This paper describes some of the research that is being done to identify potential resources, discusses some of the process involved in negotiating the broadest possible access to the material for the human language technology research community, and identifies key issues and considerations in transducing the text into Common and well documented formats.

An enantioselective, radical-based method for the intramolecular hydroamination of alkenes with sulfonamides is reported. These reactions are proposed to proceed via N-centered radicals formed by proton-coupled electron transfer (PCET) activation of sulfonamide N-H bonds. Non-covalent interactions between the neutral sulfonamidyl radical and a chiral phosphoric acid generated in the PCET event are hypothesized to serve as the basis for asymmetric induction in a subsequent C-N bond forming step, achieving selectivities of up to 98:2 er. These results offer further support for the ability of non-covalent interactions to enforce stereoselectivity in reactions of transient and highly reactive open-shell intermediates. File list (2) download file view on ChemRxiv SUBMIT.pdf (594.12 KiB) download file view on ChemRxiv SI FINAL.pdf (17.32 MiB)

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