Tetrahydrofuran → Tert-butyl 2-methyl-6-oxo-1,4-oxazepane-4-carboxylate

Temperature

30 °C

To a mixture of tert-butyl 2-methyl-6-methylene-1,4-oxazepane-4-carboxylate (2.40 g, 10.56 mmol, 1.00 eq) in THF (50.00 mL), was added NaIO4 (4.97 g, 23.23 mmol, 2.20 eq) and K2OSO4 (401.83 mg, 2.11 mmol, 0.20 eq) in one portion at 30° C. under N2. The mixture was stirred at 30° C. for 5 hours. TLC showed the reaction was completed. The mixture was poured into saturated NaSO3 (100 mL) and stirred for 5 min. The aqueous phase was extracted with ethyl acetate (30 mL*2). The combined organic phase was washed with saturated brine (30 mL*2), dried with anhydrous Na2SO4, filtered and concentrated in vacuum. The residue was purified by silica gel chromatography (Petroleum ether/Ethyl acetate=8/1) to afford tert-butyl 2-methyl-6-oxo-1,4-oxazepane-4-carboxylate (1.90 g, 8.29 mmol, 78.48% yield) as yellow oil.

1. stirringstirred for 5 min
2. extractionThe aqueous phase was extracted with ethyl acetate (30 mL*2)
3. washThe combined organic phase was washed with saturated brine (30 mL*2)
4. dry with materialdried with anhydrous Na2SO4
5. filtrationfiltered
6. concentrationconcentrated in vacuum
7. customThe residue was purified by silica gel chromatography (Petroleum ether/Ethyl acetate=8/1)

ORD record

ord-3b83e078ab2941bd9d3697519bb5b6c3

Source dataset

uspto-grants-2015_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09181288B2