2-Nitroaniline → 2-Nitrophenyl isocyanate

HRID 1767583Notes

Reaction equation

HRID 1767583 reaction equation
O=C(Cl)[O:3][C:4](Cl)(Cl)Cl.[N+:9]([C:12]1[CH:18]=[CH:17][CH:16]=[CH:15][C:13]=1[NH2:14])([O-:11])=[O:10]>CCOC(C)=O>[N+:9]([C:12]1[CH:18]=[CH:17][CH:16]=[CH:15][C:13]=1[N:14]=[C:4]=[O:3])([O-:11])=[O:10]

Participants

4

Reactant 2

HCID 69462-NitroanilineHCID 10426Diphosgene

Product 1

HCID 768342-Nitrophenyl isocyanate

Reagents, catalysts & solvents 1

HCID 8857Ethyl AcetateSolvent2×

Procedure

Method a (from 2-nitroanilines): To a solution of diphosgene (4.1 mL, 34.1 mmol) in EtOAc (40 mL) at 0° C. was added a solution of the 2-nitroaniline (45.5 mmol) in EtOAc (200–500 mL), and the mixture was heated to reflux for 18 h. The solvent was removed in vacuum to leave a brown solid, which was triturated with hot hexane (200 mL). The solid material was filtered off and the filtrate was concentrated under reduced pressure to leave the pure 2-nitrophenylisocyanate as a yellow solid. This material was refluxed in a mixture of excess tert-BuOH in CH2Cl2 for 2.5 h. Removal of the solvent left an orange solid which was purified by silica gel column chromatography with hexane/EtOAc to give the (2-nitro-phenyl)-carbamic acid tert-butyl ester as a yellow solid.

Workup

  1. temperaturethe mixture was heated
  2. temperatureto reflux for 18 h
  3. customThe solvent was removed in vacuum
  4. customto leave a brown solid, which
  5. customwas triturated with hot hexane (200 mL)
  6. filtrationThe solid material was filtered off
  7. concentrationthe filtrate was concentrated under reduced pressure

Sources & evidence

ORD record
ord-cbb03a853ce048c0a44d745a629013e3
Source dataset
uspto-grants-2007_06
Patent number
US07235547B2

Reaction notes

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