Nitric Acid → 4-fluoro-6-nitro-1,3-benzoxazol-2(3H)-one

HRID 1991335Notes

Reaction equation

HRID 1991335 reaction equation
[N+:1]([O-:4])(O)=[O:2].[F:5][C:6]1[C:11]2[NH:12][C:13](=[O:15])[O:14][C:10]=2[CH:9]=[CH:8][CH:7]=1>S(=O)(=O)(O)O>[F:5][C:6]1[C:11]2[NH:12][C:13](=[O:15])[O:14][C:10]=2[CH:9]=[C:8]([N+:1]([O-:4])=[O:2])[CH:7]=1

Participants

4

Reactant 2

HCID 944Nitric AcidHCID 450905562(3H)-Benzoxazolone,4-fluoro-(9CI)

Product 1

HCID 684892924-fluoro-6-nitro-1,3-benzoxazol-2(3H)-one

Reagents, catalysts & solvents 1

HCID 1118Sulfuric AcidSolvent

Conditions

Temperature
-10 °C

Procedure

Nitric acid (70%, 2.50 ml, 0.0389 mol) is added dropwise at −10° C. to a solution of 4-fluoro-1,3-benzoxazol-2(3H)-one (Step 4, 5.95 g, 0.0389 mol) in concentrated sulfuric acid (60 ml). The reaction is stirred at −10° C. for 30 minutes and then poured into ice water. The resulting precipitate is collected by filtration and dried under reduced pressure to give desired product contaminated with approximately 10-15% of the undesired 5-nitro isomer (7.2 g, 93%); mp 177-9° C.

Workup

  1. filtrationThe resulting precipitate is collected by filtration
  2. customdried under reduced pressure

Sources & evidence

ORD record
ord-dfec456e8f794131a3ef4e3446e51d3f
Source dataset
uspto-grants-2010_01
Patent number
US07645781B2

Reaction notes

Loading…