Dimethyl Sulfoxide → (S)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-2-oxo-oxazolidine-5-carbaldehyde

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of oxalyl chloride (0.229 mL, 2.71 mmol) in DCM (5 mL) was cooled to −78° C. and DMSO (0.395 mL, 5.572 mmol) was added dropwise. The mixture was stirred for 10 min at that temperature and a suspension of (S)-3-(2,3-dihydro-benzo[1,4]dioxin-6-yl)-5-hydroxymethyl-oxazolidin-2-one (400 mg, 1.59 mmol) in DCM (6 mL) was then added dropwise within 1 min. Stirring was continued for 20 min. TEA (0.665 mL, 4.78 mmol) was added and the mixture was stirred for 5 min, and then allowed to warm to 0° C. The mixture was filtered through Celite and concentrated with a bath temperature below 30° C. The residue was partitioned between water and EA and the org. layer was washed with brine, dried over Na2SO4 and concentrated with a bath temperature below 30° C. The highly unstable intermediate was used immediately in the next step.

Herkunft & Nachweise