Hydrochloric Acid → (+/-)-6,6-Dimethyl-bicyclo[3.1.0]hexan-2-ol

Participants

Reaction Conditions

Reaction Steps

2,2,6,6-Tetramethylpiperidine (9.70 g, 69 mmol) was taken up in MTBE (100 mL) and chilled to −78° C. n-Butyllithium (43 mL, 1.6 M in n-hexane, 69 mmol) was added cautiously and the resulting solution allowed to stir at −78° C. for 30 minutes. The pale yellow solution was added via cannular transfer to a chilled (0° C.) solution of 2-(4-methyl-pent-3-enyl)-oxirane (4.33 g, 34.3 mmol) in MTBE (30 mL) over 30 minutes, allowed to warm slowly to room temperature and stirred under argon for 18 hours. The solution was then added to 1M aqueous hydrochloric acid (50 mL) and extracted into further MTBE (200 mL). Solvent was removed under reduced pressure and the resulting oil purified by column chromatography (0-40% EtOAc/n-hexane, silica). (±)-6,6-Dimethyl-bicyclo[3.1.0]hexan-2-ol was obtained as a yellow oil. 1H NMR (CDCl3): δ 4.15-4.10 (m, 1H), 2.10-2.00 (m, 1H), 1.90-1.80 (m, 1H), 1.80-1.70 (m, 1H), 1.62 (br s, OH), 1.56 (ddd, 1H, J1=12.9, J2=9.5, J3=2.9), 1.48 (br s, 1H), 1.14 (dd, 1H, J1=6.3, J2=1.2), 0.99 (s, 3H), 0.93 (s, 3H).

Provenance & Evidence