Calcium Carbonate → benzyl N-(2-hydroxy-4-nitrophenyl)carbamate

HRID 1885492Notes

Reaction equation

HRID 1885492 reaction equation
Cl[C:2]([O:4][CH2:5][C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][CH:7]=1)=[O:3].[NH2:12][C:13]1[CH:18]=[CH:17][C:16]([N+:19]([O-:21])=[O:20])=[CH:15][C:14]=1[OH:22].C(=O)([O-])[O-].[Ca+2]>O1CCOCC1>[CH2:5]([O:4][C:2]([NH:12][C:13]1[CH:18]=[CH:17][C:16]([N+:19]([O-:21])=[O:20])=[CH:15][C:14]=1[OH:22])=[O:3])[C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][CH:7]=1

Participants

5

Reactant 3

HCID 10112Calcium CarbonateHCID 10387Benzyl chloroformateHCID 49847212-Amino-5-Nitrophenol

Product 1

HCID 14745732benzyl N-(2-hydroxy-4-nitrophenyl)carbamate

Reagents, catalysts & solvents 1

HCID 312751,4-DioxaneSolvent

Procedure

3.58 moles (536 ml) of benzyl chloroformate (95%) are added in the course of 45 minutes to 3.25 moles (500 g) of 2-amino-5-nitrophenol and 204.5 g of calcium carbonate in 1.5 liter of dioxane brought to 70° C., the temperature being maintained at between 70° C. and 80° C. When the addition is complete, heating is maintained for a further 30 minutes. The inorganic salts present in the reaction medium are removed by filtration while hot. After the addition of ice-cold water to the filtrate, the expected product crystallizes. After filtration and drying, the product obtained is recrystallized from acetic acid. It melts at 200° C.

Workup

  1. custombrought to 70° C.
  2. temperaturethe temperature being maintained at between 70° C. and 80° C
  3. additionWhen the addition
  4. temperatureheating
  5. temperatureis maintained for a further 30 minutes
  6. customThe inorganic salts present in the reaction medium are removed by filtration while hot
  7. additionAfter the addition of ice-cold water to the filtrate
  8. customthe expected product crystallizes
  9. filtrationAfter filtration
  10. customdrying
  11. customthe product obtained
  12. customis recrystallized from acetic acid

Sources & evidence

ORD record
ord-38361571fc5e413fbcca4d434e662004
Source dataset
uspto-grants-1992_09
Patent number
US05145483

Reaction notes

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