2-(Benzenesulfonyl)-3-phenyloxaziridine → Methyl 2-(2-(3-bromophenyl)-7-iodo-5-methylpyrazolo[1,5-a]pyrimidin-6-yl)-2-hydroxyacetate

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of 0.9M KHMDS/THF (2.55 mL, 2.297 mmol) in THF (8 mL) at −78° C. was added dropwise a THF (10 mL) solution of methyl 2-(2-(3-bromophenyl)-7-iodo-5-methylpyrazolo[1,5-a]pyrimidin-6-yl)acetate (859 mg, 1.767 mmol) over 5 min. After 30 min, a THF (10 mL) solution of 3-phenyl-2-(phenylsulfonyl)-1,2-oxaziridine (600 mg, 2.297 mmol) was added to the resulting red reaction mixture and stirred for additional 30 min at −78° C. Then, the resulting orange reaction mixture was quenched with sat. NH4Cl (50 mL), diluted with EtOAc (200 mL), washed with water (100 mL), brine (100 mL), dried (Na2SO4), filtered and concentrated to give light solid. This solid was triturated with small amount of ethyl acetate and solids were filtered, washed with hexanes and dried under high vacuo to afford methyl 2-(2-(3-bromophenyl)-7-iodo-5-methylpyrazolo[1,5-a]pyrimidin-6-yl)-2-hydroxyacetate (600 mg, 1.195 mmol, 67.6% yield) as light yellow solid. 1H NMR (500 MHz, CDCl3) δ: 8.21 (t, J=1.7 Hz, 1H), 7.96 (dt, J=7.8, 1.2 Hz, 1H), 7.59-7.55 (m, 1H), 7.37 (t, J=7.8 Hz, 1H), 7.09 (s, 1H), 5.78 (s, 1H), 3.87 (s, 3H), 3.54 (br. s., 1H), 2.61 (s, 3H). LCMS (M+H)=504.05.

Provenance & Evidence