Regioselective Radical Cascade Cyclizations of Alkyne-Tethered Cyclohexadienones with Chalcogenides under Visible-Light Catalysis.

Autor: Prasad VS; Department of Organic Synthesis and Process Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad 500007, Telangana, India.; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India., Ranga Rao V; Department of Organic Synthesis and Process Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad 500007, Telangana, India.; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India., Gangadhar M; Department of Organic Synthesis and Process Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad 500007, Telangana, India.; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India., Nechipadappu SK; Laboratory of X-Ray Crystallography, Department of Analytical Chemistry, CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500 007, India.; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India., Adiyala PR; Department of Organic Synthesis and Process Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad 500007, Telangana, India.; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.
Jazyk: angličtina
Zdroj: ACS omega [ACS Omega] 2023 Sep 20; Vol. 8 (39), pp. 35809-35821. Date of Electronic Publication: 2023 Sep 20 (Print Publication: 2023).
DOI: 10.1021/acsomega.3c03362
Abstrakt: Herein, we demonstrated a silver/K 2 S 2 O 8 -mediated highly regio- and diastereoselective 6/5- exo trig radical cascade cyclization of alkyne-tethered cyclohexadienones with sulfonyl hydrazides or sodium sulfinates and subsequent selenation to access 6,6-dihydrochromenone and 6,5-fused tetrahydro benzofuranone derivatives. This reaction protocol features high functional group compatibility and has a wide substrate scope providing a variety of dihydrochromenones and tetrahydro benzofuranone derivatives in good to excellent yields. The reaction proceeds via the attack of a sulfonyl radical to alkyne over the activated Michael acceptor. The TEMPO quenching experiment implies the presence of a radical intermediate. Further synthetic versatility of 6,6- and 5,6-fused derivatives is also showcased.
Competing Interests: The authors declare no competing financial interest.
(© 2023 The Authors. Published by American Chemical Society.)
Databáze: MEDLINE
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