Iodine → 3-{[1-Iodo-7-(trifluoromethyl)imidazo[1,2-a]quinoxalin-4-yl]amino}propan-1-ol

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Reaction Steps

To a 10-min stirred mixture of iodine (245 mg, 0.966 mmol, 0.6 eq) with Selectfluor™ (399 mg, 1.13 mmol, 0.7 eq) in acetonitrile (10 mL) under argon is added the 3-{[7-(trifluoromethyl)imidazo[1,2-a]quinoxalin-4-yl]amino}propan-1-ol (500 mg, 1.61 mmol, 1 eq). The dark red mixture is stirred at rt for 24 h. The precipitate is filtered out, washed with acetonitrile and dissolved in 150 mL of EtOAc. This organic phase is washed with a saturated solution of ammonium chloride, a saturated solution of sodium hydrogenocarbonate, a saturated solution of sodium hydrogen sulfite, then dried over magnesium sulfate and concentrated. A first batch of desired product is obtained as a white solid (135 mg, 0.31 mmol). To the remaining red liquor is added 0.7 additional equivalent of Selectfluor™ and 0.6 additional equivalent of iodine and the mixture is stirred under argon at rt for 16 h. Similar work-up allows the collection of a second batch (298 mg, 0.68 mmol, overall yield 62%).

Provenance & Evidence