Pivaloyl chloride → HCID 57771391, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of 3-ethoxy-3-[4-(spiro[5.5]undec-1-en-2-ylmethoxy)-phenyl]-pr opionic acid (2.95 g) obtained in Example 41 and triethylamine (3.3 mL) in tetrahydrofuran (60 mL) was added dropwise a solution of pivaloyl chloride (1.265 mL) in tetrahydrofuran (5 mL) at −35° C., followed by stirring the reaction mixture at −35 to −30° C. for 30 minutes. Then, to the reaction mixture was added dropwise a solution of (R)-4-benzyl-2-oxazolidinone (1.82 g) and lithium bromide (892 mg) in tetrahydrofuran (10 mL), followed by raising the temperature up to 0° C. over 2 hours while stirring the reaction mixture. The reaction mixture was poured into ice-cold water, followed by extraction with ethyl acetate. The organic layer was washed with saturated brine, dried and concentrated. The residue was purified by mid-pressure preparative chromatography on silica gel (ethyl acetate:hexane (volume ratio)=1:5) to give (R)-4-benzyl-3-(3-ethoxy-3-[4-(spiro[5.5]undec-1-en-2-ylmethoxy)-phenyl]-propionyl)oxazolidin-2-one.

Provenance & Evidence