Trifluoroacetic anhydride → 8-bromo-4-nitro-10-oxo-10H-chromeno[3,2-b]pyridine 1-oxide

HRID 335860Notes

Reaction equation

OO.NC(N)=[O:5].FC(F)(F)C(OC(=O)C(F)(F)F)=O.[Br:20][C:21]1[CH:34]=[CH:33][C:32]2[O:31][C:30]3[C:25](=[N:26][CH:27]=[CH:28][C:29]=3[N+:35]([O-:37])=[O:36])[C:24](=[O:38])[C:23]=2[CH:22]=1>C(Cl)Cl>[Br:20][C:21]1[CH:34]=[CH:33][C:32]2[O:31][C:30]3[C:25](=[N+:26]([O-:5])[CH:27]=[CH:28][C:29]=3[N+:35]([O-:37])=[O:36])[C:24](=[O:38])[C:23]=2[CH:22]=1

Participants

Conditions

Temperature: 0 °C

Procedure

To a suspension of urea hydrogen peroxide (58.6 mg, 0.623 mmol) in 5 mL of CH2Cl2 at 0° C. was added dropwise trifluoroacetic anhydride (87 μL, 0.623 mmol). After stirring for 5 min at 0° C., a solution of 8-bromo-4-nitro-10H-chromeno[3,2-b]pyridin-10-one (80 mg, 0.249 mmol) in CH2Cl2 (5 mL) was added and the resulting reaction was stirred at rt for 1.5 h. The mixture was carefully quenched with saturated NaHCO3 and extracted with ethyl acetate (5×5 mL). The combined organics were dried over sodium sulfate, filtered and evaporated to dryness. Purification of the crude residue by column chromatography (CH2Cl2 to CH2Cl2/EA=10:1 to 5:1) gave 8-bromo-4-nitro-10-oxo-10H-chromeno[3,2-b]pyridine 1-oxide as an light yellow solid.

Workup

customthe resulting reaction
stirringwas stirred at rt for 1.5 h
customThe mixture was carefully quenched with saturated NaHCO3
extractionextracted with ethyl acetate (5×5 mL)
dry with materialThe combined organics were dried over sodium sulfate
filtrationfiltered
customevaporated to dryness
customPurification of the crude residue by column chromatography (CH2Cl2 to CH2Cl2/EA=10:1 to 5:1)

Sources & evidence

ORD record: ord-0e469631d9bc42c084273d0099534bab
Source dataset: uspto-grants-2014_11
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08883782B2

Reaction notes

Loading…