Water → Benzyl 2-amino-4-(benzyloxy)-5-methoxybenzoate
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.S(S([O-])=O)([O-])=O.[Na+].[Na+].O.[OH-].[Na+]>C(#N)C>[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
Conditions
- Temperature
- 25 °C
Procedure
Benzyl 4-(benzyloxy)-5-methoxy-2-nitrobenzoate (77 g) was dissolved in acetonitrile (882 ml). Sodium dithionite (160.5 g) was added to the solution and the temperature adjusted to 25° C. Water (588 ml) was then added, maintaining the temperature at 25° C. The pH was maintained at 6 using 8.8 M sodium hydroxide during the reduction. The slurry was then heated to 65° C. and the lower aqueous phase was removed. Concentrated hydrochloric acid (35% w/w, 7.25 ml) was then added. The slurry was allowed to cool to 40° C. and then to 20° C. Sodium hydroxide solution (47% w/w, 12.4 ml) was added and the slurry cooled to 0° C. The product (benzyl 2-amino-4-(benzyloxy)-5-methoxybenzoate) was isolated by filtration, washed with water (2×196 ml) and then dried at 40° C. under vacuum. Yield: 66.2 g, 92.4%; 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
- customadjusted to 25° C
- temperatureThe slurry was then heated to 65° C.
- customthe lower aqueous phase was removed
- additionConcentrated hydrochloric acid (35% w/w, 7.25 ml) was then added
- temperatureto cool to 40° C.
- customto 20° C
- additionSodium hydroxide solution (47% w/w, 12.4 ml) was added
- temperaturethe slurry cooled to 0° C
Sources & evidence
- ORD record
- ord-c8cc3ac0360a4a57b2ae75af08756405
- Source dataset
- uspto-grants-2014_10
- Patent number
- US08865899B2
Reaction notes
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