Synthesis of Coumarins via [4+2] Cyclization of Siloxy Alkynes and Salicylaldehydes
Hui Qian, Jianwei Sun*
*Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, P. R. of China, Email: sunjwust.hk
H. Qian, J. Sun, Synlett, 2021, 32, 207-210.
DOI: 10.1055/s-0040-1705900
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Abstract
A benzannulation reaction of siloxy alkynes and salicylaldehydes efficiently provides a wide range of coumarins in the presence of NTf2 as catalyst. The polarized electron-rich triple bond might react sequentially with the aldehyde and hydroxy group by polarity switching in the stepwise formation of the C-C and C-O bonds.
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Key Words
coumarins, siloxy alkynes, cyclization, heterocycles
ID: J72-Y2021