Tetrahydrofuran → tert-Butyl 3,4-dihydroxypiperidine-1-carboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a stirred solution of 21 g (115 mmol) of tert-butyl 3,6-dihydropyridine-1(2H)-carboxylate from Step A in 5 mL of tetrahydrofuran was added 300 mL of water, followed by 18 g (149 mmol) of potassium chlorate. Then a solution of 200 mg of osmium tetroxide in 30 mL of water was added slowly in portions. The mixture was stirred at 80° C. for 16 h. At this time, additional portions of potassium chlorate (11.2 g, 92 mmol) and osmium tetroxide (138 mg) were added, and stirring was continued at 80° C. for another 3.5 h. The reaction mixture was partitioned between diethyl ether and water. The aqueous phase was extracted with dichloromethane and then concentrated in vacuo. The resultant residue from the aqueous phase was extracted with tetrahydrofuran. The combined organic fractions were concentrated in vacuo, and the residue was purified by flash chromatography (silica gel, 0-5% methanol/dichloromethane) to give the title compound. 1H NMR (500 MHz, CDCl3) δ 5.93 (br s, 2H), 3.92 (m, 1H)-3.83 (m, 1H), 3.63 (m, 2H), 3.39 (m, 1H), 3.25 (m, 1H), 1.84 (m, 1H), 1.72 (m, 1H), 1.47 (s, 9H). LC/MS: 240 (M+1).

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