Hydrochloric Acid → [2-(Trifluoromethoxy)phenyl]hydrazine--hydrogen chloride (1/1)

To a stirred solution of hydrochloric acid (37%, 1.6 L) at 0° C. is added 2-trifluoromethoxy-phenylamine (200 g, 113 mmol) followed by water (160 mL) and additional hydrochloric acid (160 mL). The mixture is warmed to room temperature, is stirred for 20 minutes, and is cooled to −5° C. A solution of sodium nitrite (82 g, 1.19 mmol) in water (400 mL) is added dropwise keeping the internal temperature below 0° C. The mixture is cooled to −5° C. and a solution of tin (II) chloride dihydrate (1020 g, 4520 mmol) in of HCl (37%, 3.2 L) is added dropwise keeping the internal temperature below 0° C. The mixture is warmed to room temperature, is stirred for 3 h, filtered, and washed with 6 N HCl (3 L) to obtain a yellow solid that is dried under vacuum overnight The title compound (115.8 g, 54%) is obtained pink-brown solid.

1. temperatureis cooled to −5° C
2. customthe internal temperature below 0° C
3. temperatureThe mixture is cooled to −5° C.
4. customthe internal temperature below 0° C
5. temperatureThe mixture is warmed to room temperature
6. stirringis stirred for 3 h
7. filtrationfiltered
8. washwashed with 6 N HCl (3 L)
9. customto obtain a yellow solid
10. dry with materialthat is dried under vacuum overnight The title compound (115.8 g, 54%)
11. customis obtained pink-brown solid

ORD record

ord-2ab9f760b0744494a4611815935438e3

Source dataset

uspto-grants-2010_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07846960B2