Methyl morpholine oxide → HCID 15240968, compound

Participants

Reaction Steps

To a 0° C. cooled solution of methyl 3-allyl-1-(phenylsulfonyl)-1H-indole-4-carboxylate (4.80 g, 13.50 mmol) from Step B above and N-methylmorpholine-N-oxide (2.82 g, 24.31 mmol) in a 3:1 mixture of tetrahydrofuran/water (50 mL) was added OsO4 (4 wt % in water, 5.0 mL, 54.0 mmol). The resulting mixture stirred at room temperature for 24 h, then was diluted with a saturated aqueous solution of Na2S2O5 (200 mL). The tetrahydrofuran was removed under reduced pressure and the mixture was partitioned between ethyl acetate (200 mL) and water (200 mL). The aqueous layer was extracted with ethyl acetate (3×200 mL) and the combined organic layers were washed with brine, dried (Na2SO4), filtered, and concentrated under reduced pressure. The residue was dissolved in a 3:1 mixture of tetrahydrofuran:water (50 mL), to which sodium periodate (11.55 g, 54.0 mmol) was added. The mixture stirred at room temperature for an additional 24 h. The tetrahydrofuran was removed under reduced pressure and the mixture was partitioned between ethyl acetate (200 mL) and water (200 mL). The aqueous layer was extracted with ethyl acetate (3×200 mL) and the combined organic layers were washed with brine, dried (Na2SO4), filtered, and concentrated under reduced pressure to give methyl 3-(2-oxoethyl)-1-(phenylsulfonyl)-1H-indole-4-carboxylate (2.50 g, 45%) as a crude yellow oil, which was directly elaborated without purification.

Provenance & Evidence