Hydrochloric Acid → (E)-N-benzyl-2-methylbut-2-en-1-amine

HRID 1026639Notes

Reaction equation

HRID 1026639 reaction equation
[CH2:1]([NH2:8])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[CH3:9]/[C:10](=[CH:13]\[CH3:14])/[CH:11]=O.S([O-])([O-])(=O)=O.[Mg+2].[BH4-].[Na+].Cl>C(Cl)Cl>[CH2:1]([NH:8][CH2:9]/[C:10](/[CH3:11])=[CH:13]/[CH3:14])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1

Participants

7

Procedure

Benzylamine (18.66 mmol, 2.041 ml, 2 g) was dissolved in DCM (12.00 ml). (E)-2-methylbut-2-enal (18.66 mmol, 1.803 ml, 1.570 g) and magnesium sulfate (37.3 mmol, 4.49 g) were added and the reaction mixture was stirred at room temperature for 18 hours. The resulting suspension was filtered, washing with MeOH (30 ml). The filtrate was cooled to 0° C. and sodium tetrahydroborate (93 mmol, 3.53 g) was added portionwise and the reaction mixture was then warmed to room temperature and stirred for an additional 2 hours. The reaction mixture was then acidified with 5 N HCl and organic solvents removed in vacuo. The pH was adjusted to 1 using 5 N HCl and the aqueous solution was washed with ether before addition of 4N NaOH to pH 14. The aqueous solution was then extracted with DCM (3×). The combined DCM extracts were dried over MgSO4, filtered and concentrated in vacuo to give (E)-N-benzyl-2-methylbut-2-en-1-amine (990 mg). 1H NMR (400 MHz, CDCl3) ppm 7.36-7.15 (5H, m, 5×ArH), 5.45 (1H, q, J=8 alkenyl CH), 3.73 (2H, s, CH2), 3.16 (2H, s, CH2), 1.66 (3H, s, CH3), 1.62 (3H, d, J=8, CH3).

Workup

  1. filtrationThe resulting suspension was filtered
  2. washwashing with MeOH (30 ml)
  3. temperatureThe filtrate was cooled to 0° C.
  4. temperaturethe reaction mixture was then warmed to room temperature
  5. stirringstirred for an additional 2 hours
  6. customremoved in vacuo
  7. washthe aqueous solution was washed with ether before addition of 4N NaOH to pH 14
  8. extractionThe aqueous solution was then extracted with DCM (3×)
  9. dry with materialThe combined DCM extracts were dried over MgSO4
  10. filtrationfiltered
  11. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-c8d95fdc24164deeb26cc06911d77bc3
Source dataset
uspto-grants-2014_05
Patent number
US08729274B2

Reaction notes

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