1-cyclopropyl-2-methylpropan-1-amine hydrochloride synthesis

Yield:54187-26-7 45%

Reaction Conditions:

Stage #1: 1-cyclopropyl-2-methyl-1-propanonewith ammonium acetate;sodium cyanoborohydride in methanol at 20;
Stage #2: with potassium hydroxide in methanol; for 0.166667 h;
Stage #3: with hydrogenchloride in methanol;ethanol;ethyl acetate; for 0.5 h;Cooling;

Steps:

3

Example 3 Preparation of an Amine by Reductive Amination (Precursor) A solution of 1.0 g (8.9 mmol) of cyclopropyl isopropyl ketone in 70 ml of methanol was admixed with 17.2 g (0.22 mol) of ammonium acetate and stirred at room temperature for 5 min. Thereafter, 1.7 g (26.7 mmol) of sodium cyanoborohydride were added. The mixture was stirred at room temperature for several days and then admixed with 1M potassium hydroxide solution. The flask contents were stirred for 10 min, then 40 ml of 20% sodium hydroxide solution were added. The mixture was extracted with ethyl acetate. The organic phase was acidified with hydrochloric acid, and the aqueous phase was removed and, after addition of ethyl acetate, alkalized with sodium hydroxide solution with cooling. After extraction with ethyl acetate, the organic phases were dried over magnesium sulfate, and the filtrate was admixed with 15 ml of 1.25M ethanolic HCl solution with cooling. The mixture was stirred for 30 min and then freed of the solvent under reduced pressure. 0.6 g of 1-cyclopropyl-2-methylpropylamine was isolated in the form of its hydrochloride (yield: 45%). A ¹H NMR spectrum confirms the structure.

References:

US2009/5250,2009,A1 Location in patent:Page/Page column 22-23