Methanol → tert-butyl (6R,7R)-6-(3,4-dichlorophenyl)-7-(1,2,3-trihydroxypropan-2-yl)-1,4-oxazepane-4-carboxylate

Into a solution of tert-butyl (6R,7R)-6-(3,4-dichlorophenyl)-7-(3-hydroxypent-1,4-dien-3-yl)-1,4-oxazepane-4-carboxylate (2.31 g) in methanol (50 ml) was introduced an ozone gas (from ozone developing apparatus) at −78° C. with stirring. When the solution turned pale-blue, introduction was stopped, and a nitrogen gas was introduced instead until the pale-blue color disappeared. Sodium tetrahydroborate (612 mg) was added at −78° C., and the mixture was warmed with stirring to room temperature, and stirred for 10 min. Water was added to quench the reaction, methanol was evaporated under reduced pressure, and the residue was extracted three times with ethyl acetate. The organic layer was washed with brine, and dried over anhydrous sodium sulfate, and the solvent was evaporated. The residue was purified by silica gel column chromatography (eluent; hexane:ethyl acetate (10%-100%)) to give the title compound (800 mg) as a colorless oil.

1. additiona nitrogen gas was introduced instead until the pale-blue color
2. temperaturethe mixture was warmed
3. stirringwith stirring to room temperature
4. stirringstirred for 10 min
5. customto quench
6. customthe reaction, methanol
7. customwas evaporated under reduced pressure
8. extractionthe residue was extracted three times with ethyl acetate
9. washThe organic layer was washed with brine
10. dry with materialdried over anhydrous sodium sulfate
11. customthe solvent was evaporated
12. customThe residue was purified by silica gel column chromatography (eluent; hexane:ethyl acetate (10%-100%))

ORD record

ord-fe43a4ed45c049f99a612c912ba94e08

Source dataset

uspto-grants-2014_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08722662B2