反应详情

A solution of crude 2,5-dihydro-pyrrole-1-carboxylic acid tert-butyl ester (10.5 g, 62.1 mmol) in tetrahydro-furan (300 ml) was treated sequentially with osmium tetroxide (2.5% in t-butanol, 6 mL) and N-methylmorpholine-N-oxide at 25° C. After 48 hours, aqueous 10% sodium thiosulfate solution was added and the mixture was stirred 30 minutes, partially concentrated to remove tetrahydro-furan, and the resulting aqueous mixture extracted twice with ether. The ether extracts were washed with 10% sodium thiosulfate, 0.1 N HCl, dried and concentrated giving a dark orange oil which was chromatographed on silica eluted with 1%, 2%, 4%, 8% and 10% ethanol-dichloromethane giving an amber syrup (4.09 g).

1. concentrationpartially concentrated
2. customto remove tetrahydro-furan
3. extractionthe resulting aqueous mixture extracted twice with ether
4. washThe ether extracts were washed with 10% sodium thiosulfate, 0.1 N HCl
5. customdried
6. concentrationconcentrated
7. customgiving a dark orange oil which
8. customwas chromatographed on silica
9. washeluted with 1%, 2%, 4%, 8% and 10% ethanol-dichloromethane giving an amber syrup (4.09 g)