2H-3,1-Benzoxazine-2,4(1H)-dione, 6-nitro- → 2-Amino-5-nitrobenzyl alcohol

HRID 1472974

Reaction equation

HRID 1472974 reaction equation
[N+:1]([C:4]1[CH:15]=[C:8]2[C:9](OC(=O)[NH:13][C:7]2=[CH:6][CH:5]=1)=[O:10])([O-:3])=[O:2].[BH4-].[Na+]>C(O)C.[OH-].[Na+]>[OH:10][CH2:9][C:8]1[CH:15]=[C:4]([N+:1]([O-:3])=[O:2])[CH:5]=[CH:6][C:7]=1[NH2:13]

Participants

5

Reactant 2

HCID 208212H-3,1-Benzoxazine-2,4(1H)-dione, 6-nitro-HCID 4311764Sodium borohydride

Product 1

HCID 30187062-Amino-5-nitrobenzyl alcoholYield 85.1%

Reagents, catalysts & solvents 2

HCID 702EthanolSolventHCID 14798Sodium HydroxideSolvent

Conditions

Temperature
0 °C

Procedure

5-Nitroisatoic anhydride (4.0 g, 19.22 mmol) is suspended in ethanol (32 mL) and cooled to 0° C. using an ice bath under a nitrogen atmosphere. A solution of 2.18 g (57.66 mmol) of sodium borohydride in 16 mL of 0.1 M NaOH is added dropwise over 25 minutes while keeping the temperature at 0-18° C. using an ice bath. The reaction mixture is stirred at room temperature for 3 hours, cooled in an ice bath, and carefully quenched by the addition of 6N sulfuric acid (6.5 mL) over a period of 20 minutes (0-37° C.), followed by stirring for an additional 20 minutes at 0° C. After neutralization with 6N NaOH (10 mL), the reaction mixture is poured onto 30 mL of ice water and 10 mL of 0.1 M NaOH. The orange-yellow solid is isolated by vacuum filtration and washed with water (70 mL). The resulting solid is stirred in 0.1 N NaOH (30 mL) for 95 minutes, isolated by vacuum filtration, and washed with water (3×25 mL). The yellow solid is dried under vacuum at 60° C. to constant weight, affording 2.75 g (80%) of product; 1H-NMR (300 MHz, DMSO-d6); δ 8.05 (s, 1H), 7.90 (d, J=8.6 Hz, 1H), 6.65 (d, J=8.9 Hz, 1H), 6.45 (s, 2H), 5.32 (br s, 1H), 4.39 (d, J=4.65 Hz, 2H).

Workup

  1. customat 0-18° C.
  2. temperaturecooled in an ice bath
  3. customcarefully quenched by the addition of 6N sulfuric acid (6.5 mL) over a period of 20 minutes (0-37° C.)
  4. stirringby stirring for an additional 20 minutes at 0° C
  5. additionAfter neutralization with 6N NaOH (10 mL), the reaction mixture is poured onto 30 mL of ice water and 10 mL of 0.1 M NaOH
  6. customThe orange-yellow solid is isolated by vacuum filtration
  7. washwashed with water (70 mL)
  8. stirringThe resulting solid is stirred in 0.1 N NaOH (30 mL) for 95 minutes
  9. customisolated by vacuum filtration
  10. washwashed with water (3×25 mL)
  11. customThe yellow solid is dried under vacuum at 60° C. to constant weight

Sources & evidence

ORD record
ord-5c7ec2f89a564c338166ea6fbfd12a8d
Source dataset
uspto-grants-2015_04
Patent number
US09012691B2

Linked notes

Loading…