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

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Reaction Steps

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).

Provenance & Evidence