4-(Trifluoromethoxy)aniline → p-(Trifluoromethoxy)phenol

Temperature

0 °C

p-Trifluoromethoxy aniline (49.60 g) was added rapidly dropwise to vigorously stirred 9N aqueous H2SO4 (500 mL) at 40° C. The mixture was heated to dissolve the solid, then cooled to 0° C. To the fine white suspension, a solution of sodium nitrite (19.46 g in 50 mL of H2O ) was added portionwise until an immediate positive KI/starch test result was obtained. This cold solution of diazonium salt was added rapidly dropwise to 9N aqueous H2SO4 (500 mL) at 110° C. Stirring and heating was continued for 2.5 hours. The mixture was cooled to 10° C. and extracted with diethyl ether (3×500 mL). The combined organic layers were dried (MgSO4), filtered and evaporated in vacuo, then flash chromatographed on SiO2 using diethyl ether as eluant to give 35.0 g of the desired phenol as a light brown oil. The oil was distilled (b.p.=75°-80° C. at 20 torr.) to afford a yellow liquid.

1. temperatureThe mixture was heated
2. dissolutionto dissolve the solid
3. customresult
4. customwas obtained
5. temperatureheating
6. temperatureThe mixture was cooled to 10° C.
7. extractionextracted with diethyl ether (3×500 mL)
8. dry with materialThe combined organic layers were dried (MgSO4)
9. filtrationfiltered
10. customevaporated in vacuo
11. customflash chromatographed on SiO2

ORD record

ord-8a94da0498b446a2820ea3646e878664

Source dataset

uspto-grants-1993_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05252597