Hydrogen Peroxide → 3-Bromo-6-fluorobenzene-1,2-diol

3-Bromo-6-fluoro-2-hydroxybenzaldehyde (9.0 g, 41 mmol, prepared according to Castro, Alfred C.; Depew, Kristopher M.; Grogan, Michael J.; Holson, Edward B.; Hopkins, Brian T.; Johannes, Charles W.; Keaney, Gregg F.; Koney, Nii O.; Liu, Tao; Mann, David A.; Nevalainen, Marta; Peluso, Stephane; Perez, Lawrence Blas; Snyder, Daniel A.; Tibbitts, Thomas T., WO 2008024337 A2) was stirred in 1.0 M NaOH (47 mL) and treated with hydrogen peroxide (6%; 49 g, 86 mmol). External cooling was applied to keep the temperature controlled below 50° C. After 2 h total stirring, the mixture was stirred with a solution of NaHSO3 in 50 mL water and extracted with ethyl acetate (2×75 mL). The combined extracts were washed with saturated NaCl (20 mL), dried (Na2SO4) and evaporated. The catechol derivative, as a dark orange liquid, was carried to the next step without further purification (8.9 g, qt): EIMS m/z 206.

1. temperatureExternal cooling
2. customcontrolled below 50° C
3. extractionextracted with ethyl acetate (2×75 mL)
4. washThe combined extracts were washed with saturated NaCl (20 mL)
5. dry with materialdried (Na2SO4)
6. customevaporated
7. customThe catechol derivative, as a dark orange liquid, was carried to the next step without further purification (8.9 g, qt)

ORD record

ord-a6d9107b21c946bea56b7b273bf3db09

Source dataset

uspto-grants-2015_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09149038B2