Acetonitrile → Benzyl 2-amino-4-(benzyloxy)-5-methoxybenzoate

HRID 1697849Notes

Reaction equation

HRID 1697849 reaction equation
[CH2:1]([O:8][C:9]1[C:24]([O:25][CH3:26])=[CH:23][C:12]([C:13]([O:15][CH2:16][C:17]2[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=2)=[O:14])=[C:11]([N+:27]([O-])=O)[CH:10]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.C(#N)C.S(S([O-])=O)([O-])=O.[Na+].[Na+]>O>[NH2:27][C:11]1[CH:10]=[C:9]([O:8][CH2:1][C:2]2[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=2)[C:24]([O:25][CH3:26])=[CH:23][C:12]=1[C:13]([O:15][CH2:16][C:17]1[CH:18]=[CH:19][CH:20]=[CH:21][CH:22]=1)=[O:14]

Participants

5

Reactant 3

HCID 6342AcetonitrileHCID 24489Sodium Dithionite2×HCID 10894498Benzyl 4-(benzyloxy)-5-methoxy-2-nitrobenzoate

Product 1

HCID 11057568Benzyl 2-amino-4-(benzyloxy)-5-methoxybenzoate

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Conditions

Temperature
20 °C

Procedure

Benzyl 4-(benzyloxy)-5-methoxy-2-nitrobenzoate (90 g) was charged to acetonitrile (660 g). 85% Sodium dithionite (75 g) was added to the solution and the temperature adjusted to 20° C. Water (516 g) was then added, maintaining the temperature at 20° C. The slurry was then heated to 65° C. and stirred for 30 minutes. Sodium dithionite (75 g) was added and the mixture stirred for another 30 minutes. The lower aqueous phase was removed. Concentrated hydrochloric acid (33% w/w, 12.48 g) was then added to adjust to a pH of <1. The suspension is held for 1 hour. The slurry was cooled to 20° C. over 30 minutes. Sodium hydroxide solution (20% w/w, 59.29 g) was added to give a pH of 10. The slurry was cooled to 0° C. and stirred for one hour. The product (benzyl 2-amino-4-(benzyloxy)-5-methoxybenzoate) was isolated by filtration, washed twice with water (2×222 ml) and then dried at 60° C. under vacuum. Yield: 78.81 g, 95%; NMR Spectrum (CDCl3) 3.8 (s, 3H), 5.1 (s, 2H), 5.3 (s, 2H), 6.2 (s, 1H), 7.3-7.4 (m, 10H); Mass Spectrum (M+H)+=364.1.

Workup

  1. customadjusted to 20° C
  2. temperatureThe slurry was then heated to 65° C.
  3. stirringthe mixture stirred for another 30 minutes
  4. customThe lower aqueous phase was removed
  5. additionConcentrated hydrochloric acid (33% w/w, 12.48 g) was then added
  6. waitThe suspension is held for 1 hour
  7. temperatureThe slurry was cooled to 20° C. over 30 minutes
  8. additionSodium hydroxide solution (20% w/w, 59.29 g) was added
  9. customto give a pH of 10
  10. temperatureThe slurry was cooled to 0° C.
  11. stirringstirred for one hour

Sources & evidence

ORD record
ord-c00a9611eef54111b70f39a2ec882320
Source dataset
uspto-grants-2012_04
Patent number
US08163926B2

Reaction notes

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