Triethylamine → 2-[(4-{4-[(4-Bromo-2-furyl)methyl]-5-oxo-4,5-dihydro-1,2,4-oxadiazol-3-yl}-1,2,5-oxadiazol-3-yl)amino]ethyl methanesulfonate

Participants

Reaction Steps

To a solution of 4-[(4-bromo-2-furyl)methyl]-3-{4-[(2-hydroxyethyl)amino]-1,2,5-oxadiazol-3-yl}-1,2,4-oxadiazol-5(4H)-one (7.7 g, 21 mmol, containing also some of the corresponding bromo-compound) in ethyl acetate (100 mL) was added methanesulfonyl chloride (0.96 mL, 12 mmol) in one portion. The reaction was stirred for 5 minutes and triethylamine (1.6 mL, 11 mmol) was added, also in one portion. After stirring for 30 minutes, additional methanesulfonyl chloride (0.4 mL, 5 mmol) was added, followed 5 minutes later by triethylamine (0.58 mL, 4.2 mmol). After 15 minutes, the reaction was quenched with the addition of water (100 mL). The product was extracted with ethyl acetate (3×50 mL) and the combined organic layers washed with brine (100 mL). After drying over sodium sulfate, the solvent was removed in vacuo to give the desired product (9.3 g, 100%). LCMS calculated for C12H13BrN5O7S (M+H)+: m/z=449.8, 451.8. 1H NMR (300 MHz, DMSO-d6): δ 7.88 (s, 1H), 6.73 (t, J=6.2 Hz, 1H), 6.68 (s, 1H), 5.08 (s, 2H), 4.37 (m, 2H), 3.59 (q, J=5.8 Hz, 2H), 3.16 (s, 3H).

Provenance & Evidence