P-Phenylenediamine → Benzyl N-(4-aminophenyl)carbamate

HRID 492714Notes

Reaction equation

HRID 492714 reaction equation
[NH2:1][C:2]1[CH:7]=[CH:6][C:5]([NH2:8])=[CH:4][CH:3]=1.C(N(CC)CC)C.Cl[C:17]([O:19][CH2:20][C:21]1[CH:26]=[CH:25][CH:24]=[CH:23][CH:22]=1)=[O:18].C(=O)([O-])O.[Na+]>O1CCCC1.CCCCCC.C(OCC)(=O)C>[NH2:1][C:2]1[CH:7]=[CH:6][C:5]([NH:8][C:17](=[O:18])[O:19][CH2:20][C:21]2[CH:26]=[CH:25][CH:24]=[CH:23][CH:22]=2)=[CH:4][CH:3]=1

Participants

7

Reactant 4

HCID 7814P-PhenylenediamineHCID 8471TriethylamineHCID 10387Benzyl chloroformateHCID 516892Sodium Bicarbonate

Product 1

HCID 11253521Benzyl N-(4-aminophenyl)carbamateYield 45%

Reagents, catalysts & solvents 2

HCID 8028TetrahydrofuranSolventHCID 21226206Ethyl acetate hexaneSolvent

Procedure

1,4-Diaminobenzene (1.081 g) was dissolved in tetrahydrofuran (50 ml) under a nitrogen atmosphere while stirring, and then triethylamine (2.01 ml) and benzyl chloroformate (1.71 ml) were added dropwise thereto while cooling in an ice-bath, followed by raising the temperature gradually up to room temperature. After 7 hrs, to the reaction mixture was added a saturated aqueous solution of sodium hydrogencarbonate, followed by extracting with ethyl acetate. The organic layer was washed with brine, and dried over anhydrous sodium sulfate. The solvent was evaporated under a reduced pressure to give a residue, which was then purified by silica gel column chromatography (eluent; hexane:ethyl acetate=1:1). Fractions containing the target compound were concentrated to give a residue, which was then suspended in hexane-ethyl acetate. The solid was filtered off, and dried under aeration to provide the titled compound (1.093 g, 45%) as pale yellow powder.

Workup

  1. temperaturewhile cooling in an ice-bath
  2. extractionby extracting with ethyl acetate
  3. washThe organic layer was washed with brine
  4. dry with materialdried over anhydrous sodium sulfate
  5. customThe solvent was evaporated under a reduced pressure
  6. customto give a residue, which
  7. customwas then purified by silica gel column chromatography (eluent; hexane:ethyl acetate=1:1)
  8. additionFractions containing the target compound
  9. concentrationwere concentrated
  10. customto give a residue, which
  11. filtrationThe solid was filtered off
  12. customdried under aeration

Sources & evidence

ORD record
ord-7350a891d5dd4708a4599f4db7acc3d8
Source dataset
uspto-grants-2009_05
Patent number
US07531532B2

Reaction notes

Loading…