Hydrogen Peroxide → Tert-butyl 6-(hydroxymethyl)-1,4-oxazepane-4-carboxylate

Participants

Reaction Conditions

Reaction Steps

1M borane in THF (450 mL, 0.45 mol, 0.9 eq) was added under stirring and cooling on an ice bath to a stirred in a stream of argon solution of tert-butyl 6-methylene-1,4-oxazepane-4-carboxylate (Preparation 79, 107 g, 0.5 mol, 1 eq) in THF (300 mL). The reaction mixture was heated to 25° C. and stirred at this temperature for 3 h. Then the reaction mixture was cooled to 0-10° C. and treated at this temperature sequentially with 3N sodium hydroxide (170 mL) and 30% hydrogen peroxide (66 mL). The obtained homogenous mixture was stirred overnight, then treated with hexane (45 mL), and dried over potassium carbonate. The organic layer was decanted from the precipitate, which was washed with DCM. The organic layers were evaporated in vacuo, and the residue was purified rapidly (due to instability of the product on silica gel) by chromatography (carbon tetrachloride/chloroform/isopropanol 100:0:0→0:100:0→0:90:10) on silica gel (1.2 kg; 63-100 μm) to give title compound as a colorless oil in (85 g, 0.368 mol, 72%).

Provenance & Evidence