Metal-free synthesis of phosphinoylchroman-4-ones via a radical phosphinoylation–cyclization cascade mediated by K₂S₂O₈

• Qiang Liu,
• Weibang Lu,
• Guanqun Xie and
• Xiaoxia Wang

Beilstein J. Org. Chem. 2020, 16, 1974–1982, doi:10.3762/bjoc.16.164

• Qiang Liu Weibang Lu Guanqun Xie Xiaoxia Wang Dongguan University of Technology, Dongguan 523808, P. R. China Department of Applied Chemistry, School of Science, Xi’an Jiaotong University, Xi’an 710049, P. R. China 10.3762/bjoc.16.164 Abstract A variety of chroman-4-ones bearing phosphine oxide

• afforded the title compounds in moderate yields. Keywords: chroman-4-ones; diphenylphosphine oxide; metal-free; potassium persulfate; radical cyclization; Introduction The chroman-4-one framework is a privileged structural motif found in numerous natural products and pharmaceuticals with extraordinary

• synthesize a series of phosphine oxide and phosphonate-functionalized chroman-4-ones. Unfortunately, the preparation of the substrates involved a Rh-catalyzed hydrophosphinylation of a protected functional alkyne, and the subsequent deprotection with Hg(O2CCF3)2, which is not environmentally benign (Scheme