Hexachloroethane → 5-chloro-1-(2,4-difluoro-phenyl)-1H-[1,2,4]triazole

Under an atmosphere of nitrogen a solution of 1-(2,4-difluoro-phenyl)-1H-[1,2,4]triazole (15.7 g, 86.7 mmol) in THF (300 mL) at −78° C. was treated with n-butyllithium (38 mL, 2.5 M, 95.3 mmol) dropwise. After stirring for 1.5 h a solution of hexachloroethane (22.6 g, 95.3 mmol) in THF (30 mL) was added dropwise. The resultant reaction mixture was stirred for 1.5 h before allowing to warm to RT and quenching with water. The resultant mixture was diluted with water and extracted with ethyl acetate, the combined organic extracts were dried (Na2SO4), filtered and concentrated in vacuo to give an oil which crystallised on standing. The solid was recrystallised from cyclohexane to give 5-Chloro-1-(2,4-difluoro-phenyl)-1H-[1,2,4]triazole (12.4 g, 66%). 1H NMR δ (ppm) (CDCl3): 8.04 (1 H, s), 7.51-7.43 (1 H, m), 7.10-7.04 (2 H, m).

1. additionwas added dropwise
2. customThe resultant reaction mixture
3. customquenching with water
4. additionThe resultant mixture was diluted with water
5. extractionextracted with ethyl acetate
6. dry with materialthe combined organic extracts were dried (Na2SO4)
7. filtrationfiltered
8. concentrationconcentrated in vacuo
9. customto give an oil which
10. customcrystallised
11. customThe solid was recrystallised from cyclohexane

ORD-Eintrag

ord-a880a36ba8ff4077b82913adf1df92f3

Quelldatensatz

uspto-grants-2015_12

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US09198918B2