Nitric Acid → 5-Bromo-2,4-dinitrobenzaldehyde

To ice cold conc. sulphuric acid (360 mL) was added fuming nitric acid (180 mL) dropwise followed by (ii) (60 g, 0.26 mol) dropwise over 15 min. The reaction mixture was stirred for 10 min and then allowed to warm to RT. After 30 min, the reaction mixture was heated at 45° C. for 2 h and then at 50° C. for 3 h and then allowed to cool to RT. The reaction mixture was then poured carefully over ice-water and the organics were extracted into chloroform (500 mL). The volatiles were dried (MgSO4) and concentrated in vacuo. The residue was purified by flash column chromatography eluting with EtOAc:n-hexane (gradient elution from 5% to 30% v/v) to give (iii) (5.1 g, 7%).

1. waitAfter 30 min
2. temperaturethe reaction mixture was heated at 45° C. for 2 h
3. waitat 50° C. for 3 h
4. temperatureto cool to RT
5. extractionthe organics were extracted into chloroform (500 mL)
6. dry with materialThe volatiles were dried (MgSO4)
7. concentrationconcentrated in vacuo
8. customThe residue was purified by flash column chromatography
9. washeluting with EtOAc
10. washn-hexane (gradient elution from 5% to 30% v/v)

ORD record

ord-3ede07a89b954c3cbc80bc3324444751

Source dataset

uspto-grants-2016_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09365554B2