Ammonia → 1-(3,4-Dimethylphenyl)ethan-1-amine

HRID 660050Notes

Reaction equation

HRID 660050 reaction equation
[CH3:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]([CH3:10])=O)=[CH:4][C:3]=1[CH3:11].[NH3:12].[BH4-].[Na+]>CCCO.CCCO.CCCO.CCCO.[Ti].C(OCC)(=O)C.CO>[CH3:11][C:3]1[CH:4]=[C:5]([CH:8]([NH2:12])[CH3:10])[CH:6]=[CH:7][C:2]=1[CH3:1]

Participants

6

Reactant 3

HCID 222Ammonia2×HCID 771933,4-DimethylacetophenoneHCID 4311764Sodium borohydride

Product 1

HCID 50864681-(3,4-Dimethylphenyl)ethan-1-amineYield 18%

Reagents, catalysts & solvents 2

HCID 4379755Titanium n-propoxideCatalystHCID 21584119Ethylacetate methanolSolvent

Procedure

16.4 ml (150.0 mmol) of tetrapropyl orthotitanate were added to a solution of 4.46 g (30.0 mmol) of 3,4-dimethylacetophenone in a 2 M ethanolic ammonia solution (75 ml), and the mixture was stirred for 6 hours at RT. 1.7 g (45.0 mmol) of sodium borohydride were then added, and stirring was continued for a further 16 hours at RT. Thereafter, the reaction solution was poured into a saturated aqueous ammonia solution (75 ml). The precipitate that formed was filtered off with suction, and then washing with ethyl acetate was carried out. The aqueous filtrate was concentrated in vacuo, followed by extraction twice with ethyl acetate. The combined ethyl acetate phases were extracted three times with 2 M hydrochloric acid. The combined aqueous phases were adjusted to pH 11 with a 2 M aq. NaOH solution and then extracted three times with ethyl acetate. The combined organic phases were dried over MgSO4, filtered and concentrated in vacuo. CC (ethyl acetate/MeOH 9:1) yielded 799 mg (5.4 mmol, 18%) of 1-(3,4-dimethylphenyl)ethylamine.

Workup

  1. stirringstirring
  2. waitwas continued for a further 16 hours at RT
  3. customThe precipitate that formed
  4. filtrationwas filtered off with suction
  5. washwashing with ethyl acetate
  6. concentrationThe aqueous filtrate was concentrated in vacuo
  7. extractionfollowed by extraction twice with ethyl acetate
  8. extractionThe combined ethyl acetate phases were extracted three times with 2 M hydrochloric acid
  9. extractionextracted three times with ethyl acetate
  10. dry with materialThe combined organic phases were dried over MgSO4
  11. filtrationfiltered
  12. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-ba02396c21e84cc49b866231a613e00b
Source dataset
uspto-grants-2011_12
Patent number
US08084470B2

Reaction notes

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