Atmospheric Oxygen Mediated Radical Hydrothiolation of Alkenes

• Published in: Chemistry : a European journal Vol. 26; no. 68; pp. 15804 - 15810
• Main Authors: McCourt, Ruairí O., Scanlan, Eoin M.
• Format: Journal Article
• Language: English
• Published: WEINHEIM Wiley 04.12.2020; Wiley Subscription Services, Inc
• Subjects: Alkanes; Alkenes; Alkynes; Biomolecules; Chemistry; Chemistry, Multidisciplinary; Functional groups; green chemistry; hydrothiolation; initiation; Intermediates; Oxygen; Physical Sciences; radical; Science & Technology; Sulfur; thiol-ene; radical; THIOL-ENE REACTIONS; POLYMERIZATION; PHOTOINITIATED HYDROTHIOLATION; GLYCOSYLATION; green chemistry; BETA-THIOLACTONES; THIOACIDS; initiation; BOND-DISSOCIATION ENERGIES; hydrothiolation; thiol-ene; DERIVATIVES; CYCLIZATION
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.202002542

A mild, metal‐free, atmospheric oxygen‐mediated radical hydrothiolation of alkenes (and alkyne) is reported. A variety of sulfur containing motifs including alkanethiols, thiophenols and thioacids undergo an atmospheric oxygen‐mediated radical hydrothiolation reaction with a plethora of alkenes in good yield with excellent functional group compatibility, typically with short reaction times to furnish a range of functionalized products. Biomolecules proved tolerant to the conditions and the procedure is robust and easily executable requiring no specialized equipment. Concise mechanistic studies confirm the process proceeds through radical intermediates in a thiol‐ene reaction manifold. The methodology offers an efficient “green” approach for thiol‐ene mediated “click” ligation and a milder alternative to thermally initiated hydrothiolation processes. A mild, metal‐free, atmospheric oxygen‐mediated radical hydrothiolation of alkenes is reported. A variety of sulfur containing motifs undergo thiol‐ene reaction with a plethora of alkenes in good yield with excellent functional group compatibility. Mechanistic studies confirm the process proceeds through radical intermediates. The methodology offers an efficient “green” approach for thiol‐ene mediated “click” ligation.