Water → Tert-butyl 8-tert-butyl-10-(hydroxymethyl)-11-oxa-3,8-diazaspiro[5.5]undecane-3-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of tert-butyl 8-tert-butyl-10-(1,2-dihydroxyethyl)-11-oxa-3,8-diazaspiro[5.5]undecane-3-carboxylate (1.10 g, 2.95 mmol) in tetrahydrofuran (22 mL) was added sodium periodate (1.58 g, 7.38 mmol) and water (8.0 mL), resulting in a thick white precipitate. The reaction mixture was heated at 40° C. for 3 h, then additional sodium periodate added (2.95 mmol) and the mixture stirred for 16 h. The reaction mixture was filtered through Celite and rinsed with tetrahydrofuran (30 mL). The filtrate solution was cooled to 0° C. and treated portion-wise with sodium borohydride (223 mg, 5.91 mmol) over 5 min. The reaction mixture was stirred for 30 min then diluted with brine (400 mL) and ethyl acetate (400 mL). The organic phase was separated and the aqueous phase extracted with ethyl acetate (3×100 mL). The combined organic layers were dried over Na2SO4, filtered and concentrated in vacuo. Silica gel chromatography (80 g silica, 1-10% methanol/dichloromethane) provided tert-butyl 8-tert-butyl-10-(hydroxymethyl)-11-oxa-3,8-diazaspiro[5.5]undecane-3-carboxylate (720 mg, 2.10 mmol, 71%) as colorless oil. ESI-MS m/z calc. 342.3. Found 343.5 (M+1)+; Retention time: 0.89 minutes (3 min run).

Provenance & Evidence