P-Phenylenediamine → 2-(p-Aminoanilino)benzoxazole

HRID 587420Notes

Reaction equation

HRID 587420 reaction equation
[C:1]1([NH2:8])[CH:6]=[CH:5][C:4]([NH2:7])=[CH:3][CH:2]=1.Cl[C:10]1[O:11][C:12]2[CH:18]=[CH:17][CH:16]=[CH:15][C:13]=2[N:14]=1>CN1C(=O)CCC1.O>[O:11]1[C:12]2[CH:18]=[CH:17][CH:16]=[CH:15][C:13]=2[N:14]=[C:10]1[NH:7][C:4]1[CH:5]=[CH:6][C:1]([NH2:8])=[CH:2][CH:3]=1

Participants

5

Reactant 2

HCID 7814P-PhenylenediamineHCID 119862-Chlorobenzoxazole

Product 1

HCID 4591052-(p-Aminoanilino)benzoxazoleYield 104%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 13387N-methyl-2-pyrrolidoneSolvent2×

Procedure

To a solution of benzene-1,4-diamine (5.0 g) in NMP (30 mL) was added dropwise, over 0.5 h, a solution of 2-chlorobenzo[d]oxazole (6.03 g) in NMP (50 mL). After the addition was complete, the mixture was stirred at ambient temperature for 1 h. After this time, the reaction mixture was diluted with water (200 mL) and extracted with ethyl acetate (3×200 mL). The combined organic extracts were washed with brine (150 mL), dried (Na2SO4) and filtered. The filtrate was concentrated under reduced pressure. The residue obtained was purified by chromatography (silica, methylene chloride to 1:19 methanol/methylene chloride) to afford N-(1,3-benzoxazol-2-yl)benzene-1,4-diamine (9.20 g) as an off-white solid.

Workup

  1. additionAfter the addition
  2. extractionextracted with ethyl acetate (3×200 mL)
  3. washThe combined organic extracts were washed with brine (150 mL)
  4. dry with materialdried (Na2SO4)
  5. filtrationfiltered
  6. concentrationThe filtrate was concentrated under reduced pressure
  7. customThe residue obtained
  8. customwas purified by chromatography (silica, methylene chloride to 1:19 methanol/methylene chloride)

Sources & evidence

ORD record
ord-e2b84ed758124fdcac8b4ca2850338b1
Source dataset
uspto-grants-2016_01
Patent number
US09226921B2

Reaction notes

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