Acetic acid, 2-oxo-, methyl ester → HCID 19873307, compound

Temperature

-70 °C

In the same manner as in Example 1, a solution of an (R)-binaphthol-dichlorotitanium complex was obtained. This solution was cooled to -70° C. in a dry ice-acetone bath. To this solution were successively added 88 mg (1 mmole) of methyl glyoxylate and 196 mg (2 mmole) of 1-methoxy-1,3-pentadiene. Reaction was then allowed to proceed at -10° C. for 1 hour, and 10 ml of a sodium hydrogencarbonate aqueous solution was added to the reaction mixture to terminate the reaction. This reaction mixture was filtered through Celite and then subjected to extraction once with 20 ml of diethyl ether and twice with 20 ml of ethyl acetate. The extract was dried over anhydrous magnesium sulfate. Thereafter, the solvent was removed by evaporation, and the residue was purified by silica gel column chromatography (200 mesh; developing solvent: hexane/ethyl acetate =10/1), thereby obtaining 0.23 g of desired optically active 2-methoxy-6-methoxycarbonyl-5-methyl-5,6-dihydropyran (yield: 63%).

1. customIn the same manner as in Example 1, a solution of an (R)-binaphthol-dichlorotitanium complex was obtained
2. customReaction
3. customto terminate
4. customthe reaction
5. filtrationThis reaction mixture was filtered through Celite
6. extractionsubjected to extraction once with 20 ml of diethyl ether and twice with 20 ml of ethyl acetate
7. dry with materialThe extract was dried over anhydrous magnesium sulfate
8. customThereafter, the solvent was removed by evaporation
9. customthe residue was purified by silica gel column chromatography (200 mesh; developing solvent: hexane/ethyl acetate =10/1)
10. customobtaining 0.23 g

ORD record

ord-510763ab987f45129c184307561f7fc2

Source dataset

uspto-grants-1992_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05155240