Ammonium Chloride → (R)-3-((S)-4-(2,4-difluoro phenyl)-2-(hydroxymethyl)pent-4-enoyl)-4-phenyloxazolidin-2-one

Participants

Reaction Conditions

Reaction Steps

Titanium chloride solution (prepared from 33.8 ml of titanium chloride and 50 ml of dichloromethane) was added to a pre-cooled solution of (R)-3-(4-(2,4-difluorophenyl)pent-4-enoyl)-4-phenyloxazolidin-2-one compound of formula-4 (100 g) in dichloro methane (1000 ml) at −20 to −10° C. under nitrogen atmosphere and diisopropyl ethylamine (45.61 μm) was added to the reaction mixture and stirred for 40 minutes at −20 to −10° C. A trioxane solution (prepared from 52.94 g of trioxane and 150 ml of dichloro methane) was added to the reaction mixture at −20 to −10° C. and followed by titanium chloride solution (prepared from 33.8 ml of titanium chloride and 50 ml of dichloro methane) at −20 to −10° C. Temperature of the reaction mixture was raised to −5 to 0° C. and stirred for 2 hours at −5 to 0° C. After completion of the reaction, the reaction mixture was added to 10% ammonium chloride at 10-15° C. Both organic and aqueous layers were separated and the aqueous layer was extracted with dichloro methane. Both the dichloro methane layers were combined and washed with water followed by 10% sodium chloride solution. The obtained dichloro methane layer was taken to the next step without isolating the title compound.

Provenance & Evidence