Diethyl Ether → (S)-1-(3-(hydroxymethyl)piperidin-1-yl)-3-methylbutan-1-one

Participants

Reaction Conditions

Reaction Steps

(S)-piperidin-3-ylmethanol hydrochloride (10 g, 65.95 mmol) in water (25 mL) was treated dropwise at 0° C. with a solution of NaOH (13.2 g, 330 mmol, 5 eq.) in water (25 mL). The mixture was stirred for 15 min and a solution of isovaleryl chloride (15.90 g, 131.9 mmol, 2 eq.) in anhydrous THF (25 mL) was added dropwise while stirring vigorously. After 30 minutes at 0° C. the reaction was slowly warmed up to room temperature and stirred overnight. Et2O (500 mL) was added to the reaction mixture with vigorous stirring. The organic layer was separated and washed with brine, dried over Na2SO4 and concentrated to give a residue that was purified by chromatography on silica (Hex/EtOAc 0-100 to yield the desired compound as a colorless oil (16.27 g, 82.62 mmol, 94%). 1H NMR (400 MHz, DMSO-d6, 20° C.) δ 0.88 (pseudo d, J=6.4 Hz, 6H), 1.06-1.75 (m, 5H), 1.88-2.05 (m, 1H), 2.07-2.23 (m, 2H), 2.30 (dd, J=10.8, 12.8 Hz, 0.5H), 2.64 (ddd, J=3.2, 10.8, 13.2 Hz, 0.5H), 2.78 (dd, J=10.4, 13.2 Hz, 0.5H), 2.93 (ddd, J=2.4, 11.6, 13.6 Hz, 0.5H), 3.14-3.35 (m, 2H), 3.70-3.85 (m, 1H), 4.08-4.18 (dm, 0.5H), 4.31-4.40 (dm, 0.5H), 4.49 (t, J=5.2 Hz, 0.5H), 4.58 (t, J=5.2 Hz, 0.5H). MS 200 (MH+).

Provenance & Evidence