Hydrochloric Acid → (S)-4,4-Dimethylpyrrolidin-3-OL hydrochloride

Reaction equation

C([N:8]1[CH2:12][C:11]([CH3:14])([CH3:13])[C@H:10]([OH:15])[CH2:9]1)C1C=CC=CC=1.[ClH:16]>C(O)C.[Pd]>[ClH:16].[CH3:13][C:11]1([CH3:14])[CH2:12][NH:8][CH2:9][C@H:10]1[OH:15]

Participants

Procedure

A solution of 6.34 g (41.7 mmol) of (3S)-1-benzyl-4,4-dimethyl-3-pyrrolidinol in 250 mL of ethanol and 50 mL of 1N hydrochloric acid was stirred under hydrogen (40 psi) for 18 h in the presence of 300 mg of 10% Pd/C, after which the amount of 10% Pd/C was doubled and 2 mL of concentrated hydrochloric acid were added. The mixture was stirred for an additional 72 h under hydrogen (40 psi), before the 10% Pd/C was filtered off over celite. The filtrate was concentrated and several portions of toluene were distilled from the residue, which was then dried under high vacuum to afford 4.74 g (quantitative yield) of (3S)-4,4-dimethyl-3-pyrrolidinol hydrochloride. 1H NMR (300 MHz, DMSO-d6) δ 9.46 (m, 2H), 5.43 (br s, 1H), 3.75 (m, 1H), 3.36 (m, 1H), 2.88 (m, 3H), 0.98 (s, 3H), 0.94 (s, 3H).