Benzylamine → 245759-64-2

HRID 380247Notes

Reaction equation

HRID 380247 reaction equation
[CH3:1][O:2][C:3]1[CH:8]=[CH:7][C:6]([CH2:9][C:10](=O)[CH3:11])=[CH:5][CH:4]=1.[CH2:13]([NH2:20])[C:14]1[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=1.[H][H].[C:23]([OH:33])(=[O:32])[C@H:24]([C:26]1[CH:31]=[CH:30][CH:29]=[CH:28][CH:27]=1)[OH:25]>[Pt].CO>[C:23]([OH:33])(=[O:32])[C@H:24]([C:26]1[CH:31]=[CH:30][CH:29]=[CH:28][CH:27]=1)[OH:25].[CH3:1][O:2][C:3]1[CH:8]=[CH:7][C:6]([CH2:9][CH:10]([CH3:11])[NH:20][CH2:13][C:14]2[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=2)=[CH:5][CH:4]=1

Participants

7

Conditions

Temperature
45 °C

Procedure

To 800 mL of methanol were added 328 g of 4-methoxyphenylacetone (2 mol) and 214 g of N-benzylamine (2 mol). The imine formation was exothermic and the solution warmed to 45° C. After reaction was complete. the solution was hydrogenated at 50 psi for 6-8 hours in the presence of 3.3 g of 5% platinum on carbon catalyst. When the hydrogen uptake had stopped, the reaction was filtered through diatomaceous earth, and the filter cake was washed with 200 mL of methanol. The combined filtrates were placed in a 6-liter flask and diluted with 4.2 liters of methanol. (S)-L-Mandelic acid (304 g, 2 mol) was added and the mixture heated with stirring to reflux to obtain a clear solution. The solution was cooled to room temperature, stirred at room temperature for two hours and the mandelic acid salt filtered off. The recrystallization was repeated three times to obtain 60-70 g of 4-methoxy-α-methyl-N-(phenylmethyl)benzeneethaneamine L-mandelic acid salt having an isomeric purity greater than 99.8% and a melting point of 164° C.

Workup

  1. customAfter reaction
  2. filtrationthe reaction was filtered through diatomaceous earth
  3. washthe filter cake was washed with 200 mL of methanol
  4. customThe combined filtrates were placed in a 6-liter flask
  5. additiondiluted with 4.2 liters of methanol
  6. temperaturethe mixture heated
  7. temperatureto reflux
  8. customto obtain a clear solution
  9. temperatureThe solution was cooled to room temperature
  10. stirringstirred at room temperature for two hours
  11. filtrationthe mandelic acid salt filtered off
  12. customThe recrystallization

Sources & evidence

ORD record
ord-eb482e8ce96b4b7eb71a145c3ff60d7b
Source dataset
uspto-grants-2001_10
Patent number
US06303145B2

Reaction notes

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