Ammonium Chloride → (3aR,5S,6aR)-2,2-dimethyl-5-[(2R)-oxiran-2-yl]-3a,5,6,6a-tetrahydrofuro[2,3-d][1,3]dioxole

Participants

Reaction Conditions

Reaction Steps

To a solution of [(2R)-2-[(3aR,5S,6aR)-2,2-dimethyl-3a,5,6,6a-tetrahydrofuro[2,3-d][1,3]dioxol-5-yl]-2-hydroxy-ethyl] 4-methylbenzenesulfonate (compound 6a, 100 g, 280 mmol) in anhydrous THF (1500 mL) cooled at −70° C. was added potassium bis(trimethylsilyl)amide (340 mL, 340 mmol, 1 M in THF) under N2 atmosphere. After being stirred at −70° C. for 1 hour, the reaction mixture was poured into saturated NH4Cl solution. The organic layer was separated and the aqueous phase was extracted with EtOAc. The combined organic layers were dried over Na2SO4 and concentrated in vacuo. The residue was purified by column chromatography on silica gel (eluting with 1:3 EtOAc in petroleum ether) to afford 40.5 g of (3aR,5S,6aR)-2,2-dimethyl-5-[(2R)-oxiran-2-yl]-3a,5,6,6a-tetrahydrofuro[2,3-d][1,3]dioxole (compound 6b) as a slight yellow oil.

Provenance & Evidence