A highly efficient -dearomative cyclization reaction between alkynes and 2-bromo-2-(2-methoxybenzyl)malonate via visible light-induced photoredox catalysis has been reported. In the presence of 1 mol % -Ir(ppy), a variety of spiro[4.5]deca-1,7,9-trien-6-ones were obtained in moderate to excellent yields under mild conditions. Under the optimized reaction conditions, a sample reaction of 3 mmol scale proceeded smoothly to give the desired products in 84% yield with a low catalyst loading of 0.1 mol %.
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Spiro-meroterpenoids, Syzygioblanes D-H, Isolated from Indonesian Medicinal Plant .
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School of Pharmaceutical Sciences, College of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa 920-1192, Japan.
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Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education), Key Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan Province, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha, Hunan 410081, China.
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