Oxalyl chloride → HCID 81430882, compound

Temperature

-20 °C

(I4B): Anhydrous DMF (242 ml) was cooled to −20° C. in a dry ice/acetone bath and the internal temperature was monitored carefully and maintained at or below this temperature. Neat oxalyl chloride (9.51 ml, 109 mmol) was then slowly added dropwise via addition funnel and the vessel was properly vented to allow the escape of gases generated. Following the addition, the cloudy-white suspension was stirred at −20° C. for 30 min. A solution containing methyl 3-bromo-4-hydroxy-5-nitrobenzoate (10 g, 36.2 mmol) in DMF (121 ml) was then added slowly, not allowing the internal temp to exceed −10° C. Following the addition, the suspension was warmed to room temperature and then heated to 100° C. for 2 h. The reaction was cooled to room temperature and stirred over weekend. The dark brown solution was poured into ice water and diluted with EtOAc. The aqueous phase was extracted twice with EtOAc. The combined organics were washed with water and brine, and then dried over anhydrous sodium sulfate. Filtration and concentration afforded methyl 3-bromo-4-chloro-5-nitrobenzoate (10 g) as a yellow solid that was dried in vacuo overnight.

1. temperaturemaintained at or below this temperature
2. additionthe addition
3. additionwas then added slowly
4. customto exceed −10° C
5. additionthe addition
6. temperaturethe suspension was warmed to room temperature
7. temperatureheated to 100° C. for 2 h
8. temperatureThe reaction was cooled to room temperature
9. stirringstirred over weekend
10. extractionThe aqueous phase was extracted twice with EtOAc
11. washThe combined organics were washed with water and brine
12. dry with materialdried over anhydrous sodium sulfate
13. filtrationFiltration and concentration

ORD record

ord-4cac21b6ac934d42842c30b2ab10febd

Source dataset

uspto-grants-2016_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09273057B2