Hydrochloric Acid → trans-5,5-Difluorooctahydrocyclopenta[b][1,4]oxazine hydrochloride

Participants

Reaction Steps

Trans-4-benzyl-5,5-difluorooctahydrocyclopenta[b][1,4]oxazine (350 mg, 1.38 mmol) was dissolved in MeOH (10 mL). 3M HCl in MeOH (1.5 mL) was added and the solution was stirred for 1 hour. The solvent was evaporated and further azeotroped using toluene. The residue was then dissolved in MeOH (10 mL), and 20% Pd(OH)2/C (20% by wt, 50 mg) added. Hydrogen was purged through the reaction for 10 minutes and stirring was continued at room temperature under 1 atm of hydrogen for 16 hours. The reaction was filtered through celite, and the filtrate was concentrated to afford trans-5,5-difluorooctahydrocyclopenta[b][1,4]oxazine hydrochloride. 1H NMR (400 MHz, CD3OD) δ 4.16 (dd, J=13.6, 4.0 Hz, 1H), 3.78-3.92 (m, 2H), 3.65 (m, 1H), 3.43 (dd, J=13.2, 2.4 Hz, 1H), 3.28-3.31 (m, 2H), 2.15-2.55 (m, 2H), 1.89 (m, 1H). MS ESI calc'd. for C7H11F2NO [M+H]+ 164. found 164.

Provenance & Evidence