N,N-Diethyl-1,1,2,3,3,3-hexafluoropropylamine → (4S,5R)-3-propionyl-2,2-dimethyl-4-fluoromethyl-5-[4-(methylsulfonyl)phenyl]-1,3-oxazolidine

Participants

Reaction Conditions

Reaction Steps

(4R,5R)-3-propionyl-2,2-dimethyl-4-hydroxymethyl-5-[4-(methylsulfonyl)phenyl]-1,3-oxazolidine (Compound V: R1 is methylsulfonyl, R2 and R3 are methyl and R4 is ethyl) (70 g, 0.2050 moles) in methylene chloride (450 ml) reacts with N,N-diethyl-1,1,2,3,3,3-hexafluoro-1-propanamine (Ishikawa Reagent) (73.2 g, 0.328 moles) at 95-105° C. for 2-4 hours. Cooling to 20-25° C., quenching with 25% aqueous sodium hydroxide and water (2000 mL) and separation of the methylene chloride layer gives a solution of (4S,5R)-3-propionyl-2,2-dimethyl-4-fluoromethyl-5-[4-(methylsulfonyl)phenyl]-1,3-oxazolidine (Compound IX: R1 is methylsulfonyl, R2 and R3 are methyl and R4 is ethyl) for use in the next step.

Provenance & Evidence