1-Butanol → Benzeneethanamine, N-[2-(3,4-dimethoxyphenyl)ethyl]-3,4-dimethoxy-

HRID 1031989Notes

Reaction equation

HRID 1031989 reaction equation
[BH4-].[Na+].[CH3:3][O:4][C:5]1[CH:6]=[C:7]([CH2:13][CH2:14][NH:15][C:16](=O)[CH2:17][C:18]2[CH:23]=[CH:22][C:21]([O:24][CH3:25])=[C:20]([O:26][CH3:27])[CH:19]=2)[CH:8]=[CH:9][C:10]=1[O:11][CH3:12].C(O)CCC>O1CCCC1.O.C(O)(=O)C.C(O)C>[CH3:27][O:26][C:20]1[CH:19]=[C:18]([CH2:17][CH2:16][NH:15][CH2:14][CH2:13][C:7]2[CH:8]=[CH:9][C:10]([O:11][CH3:12])=[C:5]([O:4][CH3:3])[CH:6]=2)[CH:23]=[CH:22][C:21]=1[O:24][CH3:25]

Participants

8

Reactant 3

HCID 2631-ButanolHCID 67318N-(3,4-Dimethoxyphenethyl)-2-(3,4-dimethoxyphenyl)acetamideHCID 4311764Sodium borohydride

Product 1

HCID 29749Benzeneethanamine, N-[2-(3,4-dimethoxyphenyl)ethyl]-3,4-dimethoxy-Yield 75%

Reagents, catalysts & solvents 4

HCID 176Acetic AcidSolvent2×HCID 702EthanolSolventHCID 962WaterSolventHCID 8028TetrahydrofuranSolvent

Conditions

Temperature
10 °C

Procedure

37.7 g of sodium borohydride are suspended in 1500 cc of anhydrous tetrahydrofuran in an inert atmosphere of nitrogen. To the suspension are added 36 g of amide prepared in part (b), while the mixture is stirred and cooled to 10° C., and there is added also 58 cc of glacial acetic acid. The mixture is warmed under reflux for four hours. At the end of this period, the solvent is evaporated under reduced pressure and the residue is treated with water and then with dilute hydrochloric acid to a full acidity. To the mixture is then added a solution of sodium hydroxide until the pH is alkaline and the material is extracted four times with 300 cc each time of dichloromethane. The organic phase is extracted with dilute hydrochloric acid, the acetic solution is washed with dichloromethane. It is then cooled and made alkaline with potassium carbonate and finally extracted again with four portions of dichloromethane, using 200 cc each time. The organic phase is dried over anhydrous sodium sulfate, filtered and evaporated. The residue is the crude amine which is recrystallized from ethanol thus giving a pure product, 28.5 g, yield 75%; m.p. 56°-58° C. A single spot is obtained on T.L.C. (eluent: n-butanol, ethanol, acetic acid, water 60:20:40:10).

Workup

  1. temperatureThe mixture is warmed
  2. temperatureunder reflux for four hours
  3. customAt the end of this period, the solvent is evaporated under reduced pressure
  4. additionthe residue is treated with water
  5. additionTo the mixture is then added a solution of sodium hydroxide until the pH
  6. extractionthe material is extracted four times with 300 cc each time of dichloromethane
  7. extractionThe organic phase is extracted with dilute hydrochloric acid
  8. washthe acetic solution is washed with dichloromethane
  9. temperatureIt is then cooled
  10. extractionfinally extracted again with four portions of dichloromethane
  11. dry with materialThe organic phase is dried over anhydrous sodium sulfate
  12. filtrationfiltered
  13. customevaporated
  14. customis recrystallized from ethanol
  15. customthus giving a pure product, 28.5 g, yield 75%
  16. customA single spot is obtained on T.L.C

Sources & evidence

ORD record
ord-cba4e83ddddd44c8816cbc583c6944ca
Source dataset
uspto-grants-1990_09
Patent number
US04956389

Reaction notes

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