An organo-photocatalyzed visible-light-driven multi-component approach for carbothioaryl/alkylation of activated
Debabrata Das1, Krishna Gopal Ghosh1, Sumit Garai1
1Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur-741246, West Bengal, India. suresh@iiserkol.ac.in.
Abstract:
A visible-light-driven organophotocatalyzed multi-component approach for carbothiolation of activated alkenes is demonstrated under environmentally benign and redox-neutral conditions, involving direct C(sp3)-H functionalization followed by electrophilic alkyl/arylthiolation. The three-component difunctionalization reaction is a complete transition-metal and peroxide-free process conducted under milder conditions. In this composite reaction, by employing bench-stable reagents, the formation of two new C(sp3)-C(sp3) and C(sp3)-S bonds is achieved for a wide variety of substrates, showcasing the excellent functional group tolerance and chemoselectivity of the methodology. Furthermore, the scalability and utilization of natural sunlight instead of artificial blue LEDs, along with the use of an inexpensive and easy-to-prepare pyrylium salt as an organo-photocatalyst, make this protocol greener and more energy efficient.
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