HCID 11076344, compound → HCID 10967937, compound

0.05 M Na2HPO4 aqueous solution (16.6 ml) was added to 0.55 M NaOCl aqueous solution (41.5 ml, 22.8 mmol) at 0° C. To the aqueous solution was slowly added the solution of (2S)-6-nitro-2-methyl-2-dimethoxymethyl-2H-1-benzopyran (1.5 g, 5.7 mmol) and (S,S)-Mn(III) salen, catalyst (155 mg, 0.28 mmol) for an enantioselective epoxidation developed by Jacobsen in dichloromethane (8.5 ml). The solution was stirred at the room temperature for 12 hours. After the reaction was completed, the reaction mixture was filtered to remove the catalyst and the filtrate was extracted with dichloromethane (200 ml). The dichloromethane layer was washed with saturated brine solution, dried over anhydrous magnesium sulfate and concentrated to remove the dichloromethane. The crude product was purified by chromatography (developing solvent—n-hexane:ethyl acetate=4:1) to give (2S,3S,4S)-6-nitro-2-methyl-2-dimethoxymethyl-3,4-epoxy-3,4-dihydro-2H-1-benzopyran, the compound of formula 2 (1.4 g, yield: 88%).

1. filtrationthe reaction mixture was filtered
2. customto remove the catalyst
3. extractionthe filtrate was extracted with dichloromethane (200 ml)
4. washThe dichloromethane layer was washed with saturated brine solution
5. dry with materialdried over anhydrous magnesium sulfate
6. concentrationconcentrated
7. customto remove the dichloromethane
8. customThe crude product was purified by chromatography (developing solvent—n-hexane:ethyl acetate=4:1)

ORD record

ord-f2c5bb22bdb44297b67172d626caa23a

Source dataset

uspto-grants-2008_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07414068B2