Reacción #90558

Ecuación de reacción

3,5-dibromo pyridine

isopropyl magnesium chloride

Hexafluoroacetone

→

2-(5-bromopyridin-3-yl)-1,1,1,3,3,3-hexafluoropropan-2-ol

Disolventes

THF

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.STIRRINGcontinued stirring for another 2 h
2. 2
   OtroAfter completion of the starting materials, the reaction was quenched with saturated ammonium chloride solution
3. 3
   OtroThe organic layer was separated
4. 4
   Extracciónaqueous phase was extracted again with diethyl ether
5. 5
   Secadothe combined organic layer was dried over sodium sulphate
6. 6
   Concentraciónconcentrated

Procedimiento

To a stirred solution of 3,5-dibromo pyridine 257 (1.09 g, 4.60 mmol) in dry THF cooled to 0° C., was added isopropyl magnesium chloride (2.4 mL, 4.8 mmol) drop wise while stirring for 10 min. Hexafluoroacetone (CF3—CO—CF3) 244 was added to the resulting reaction and continued stirring for another 2 h. After completion of the starting materials, the reaction was quenched with saturated ammonium chloride solution. The organic layer was separated and aqueous phase was extracted again with diethyl ether, the combined organic layer was dried over sodium sulphate and concentrated to get the crude 2-(5-bromopyridin-3-yl)-1,1,1,3,3,3-hexafluoropropan-2-ol 258. The crude was purified through silica gel by using 100-200 mesh silica gel by eluting the compound at 20:5 ethyl acetate in hexane as thick oil of compound 258.

Fuente