Synthesis of 3-isoxazolines
The use of tetrabutylammonium fluoride (TBAF) enables a versatile approach to isoxazolines and pyrazolines by the cyclization of alkyne substrates under mild reaction conditions. A deprotection/functionalization method is described, leading to a substituted pyrazoline in good diastereoselectivity.
E. Nagy, S. D. Lepore, Org. Lett., 2017, 19, 3695-3698.
A Cu(I)-catalyzed three-component reaction of terminal alkynes, trifluoromethyl diazo compounds, and nitrosoarenes provides a series of trifluoromethyl-substituted dihydroisoxazoles in high yields under mild reaction conditions.
X. Lv, Z. Kang, D. Xing, W. Hu, Org. Lett., 2018, 20, 4843-4847.