Abstract
A general method for the liquid-phase syntheses of isoxazoles
and isoxazolines through a 1,3-dipolar cycloaddition is described.
The poly(ethylene glycol) (PEG)-supported alkyne 2 or alkene 6 reacted with nitrile oxides generated
in situ from aldoximes 3 , followed by cleavage
from the PEG, to give isoxazoles or isoxazolines in good yield and
purity.
Key words
poly(ethylene glycol) - isoxazolines - isoxazoles - cycloaddition - liquid-phase
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