tert-Butyl hydroperoxide → 3-[[(1,1-Dimethylethyl)dimethylsilyl]oxy]-2-[(phenylmethoxy)methyl]-6-oxabicyclo[3.1.0]hexane-1-methanol

Beteiligte Stoffe

Reaktionsschritte

A 250-mL oven dried three necked round bottomed flask was equipped with a magnetic stir bar, argon inlet, and temperature probe charged with oven dried powdered molecular sieves 4A° (9.0 g). DCM (30 mL) was added to the flask and the resulting suspension was stirred room temperature for 5 minutes. Diethyl D-tartrate (2.13 g, 10.32 mmol) in DCM (18 mL) was added at room temperature and the mixture was cooled to −30° C. Keeping the temperature at −30° C., titanium (IV) isopropoxide (2.665 mL, 9.03 mmol) was added. The reaction mixture was stirred at −30° C. for 30 minutes followed by 15 minutes at −15° C. The mixture was cooled to −30° C. To this mixture, a solution of compound 16 (4.5 g, 12.9 mmol) in DCM (18 mL) was added. The mixture was stirred for 30 minutes at −30° C. followed by addition of a solution of tert-butyl hydroperoxide (5.0–6.0 M; 9.40 mL, 5.176 mmol). The reaction mixture was stirred between −30° C. to −20° C. for 3 hours to complete the reaction. The reaction was quenched by addition of water (45 mL). The reaction mixture was stirred with vigorous mixing and allowed to warm up to room temperature (15 to 20° C). When the temperature reached ˜15° C., 30% sodium hydroxide solution (10 mL) was added slowly to give a milky white slurry. This slurry was added into a 3.0-L Erlenmeyer flask containing tert-butyl methyl ether (1100 mL). The mixture was stirred for 30 minutes and then filtered on a bed of diatomaceous earth (Celite®). The aqueous layer was separated from the filtrate and discarded. The organic layer was washed with 10% aqueous sodium thiosulfate (100 mL) and water (2×160 mL). The combined organic layer was washed with water (100 mL), brine (50 mL), and dried over magnesium sulfate. The organic layer was concentrated in vacuo to give the title compound in quantitative yield (5.47 g) as an oil.

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