4-Bromobenzene-1,2-diamine → HCID 178506219, compound

A 5-L 4-neck round bottom flask equipped with a thermocouple, mechanical stirrer and an argon inlet adapter was charged with 4-bromo-1,2-phenylenediamine (166.4 g, 0.863 mol), ethanol (2 L), followed by the addition of 2-(4-trifluoromethyl-phenoxy)-acetimidic acid ethyl ester hydrochloride (272.0 g, 0.959 mol) and ethanol (0.9 L). The initial solution of diamine turned to a suspension upon the addition of 2-(4-trifluoromethyl-phenoxy)-acetimidic acid ethyl ester hydrochloride, and an exotherm from 17° C. to 28° C. was noted. The reaction was assayed at 2.5 h and found to be complete. The reaction was filtered though Celite (60 g) and the gray solid was washed with ethanol (200 mL) until the filtrates were no longer colored. A clean 12-L 4-neck round bottom flask equipped with a mechanical stirrer, a 1-L addition funnel and ice bath for cooling was set-up and the ethanol filtrates were transferred into the 12-L flask. While cooling the flask, water (3.5 L) was added to the ethanol, and the resulting brown suspension was stirred for 1 h in the ice bath to enhance recovery. The brown solid was filtered evenly between two Buchner funnels, each washed with cold water (150 mL, 2×200 mL), and the brown solid was air-dried for a few hours. The brown solid was transferred to two amber bottles, dried in a hi-vac oven (60 mm) at 60° C., to a constant weight and afforded a total of 331.9 g (103% isolated yield; 97.7-98%, HPLC area %) of the title compound as a brown powder.

1. customA 5-L 4-neck round bottom flask equipped with a thermocouple, mechanical stirrer and an argon inlet adapter
2. customfrom 17° C. to 28° C.
3. filtrationThe reaction was filtered though Celite (60 g)
4. washthe gray solid was washed with ethanol (200 mL) until the filtrates
5. customA clean 12-L 4-neck round bottom flask equipped with a mechanical stirrer
6. additiona 1-L addition funnel and ice bath
7. temperaturefor cooling
8. temperatureWhile cooling the flask, water (3.5 L)
9. additionwas added to the ethanol
10. filtrationThe brown solid was filtered evenly between two Buchner funnels
11. washeach washed with cold water (150 mL, 2×200 mL)
12. customthe brown solid was air-dried for a few hours
13. customdried in a hi-vac oven (60 mm) at 60° C.
14. customto a constant weight and afforded

ORD record

ord-02e3c77fd39d4743b42a20094edda923

Source dataset

uspto-grants-2009_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07612211B2