Water → [2-(4,5-Diiodo-2-propylimidazol-1-yl)ethyl]carbamic acid tert-butyl ester

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Reaction Steps

To a solution of 4,5-diiodo-2-propyl-1H-imidazole (15.000 g; 41.443 mmol) in anhydrous DMF (260 ml) was added portionwise, at rt, 55-65% sodium hydride moistened with oil (1.989 g; 49.732 mmol). The resulting mixture was further stirred at rt, under nitrogen, for 20 min. The mixture was then heated to 100° C., and a colorless homogeneous solution of 2-(Boc-amino)-ethylbromide (10.216 g; 45.587 mmol) in anhydrous DMF (100 ml) was added dropwise, over 1 h, with an addition funnel. After completion of the addition, the resulting dark-orange homogeneous mixture was further heated at 100° C. for 1 h30. The reaction mixture was cooled to rt, and water (300 ml) was added slowly. This mixture was extracted with ether (3×200 ml). The combined organic layers were washed with brine (2×100 ml), dried over anh. MgSO4, filtered, and concentrated to dryness under reduced pressure to give a yellow oil. The crude was purified by FC (heptane/EA=1/1) to give the pure product [2-(4,5-diiodo-2-propyl-imidazol-1-yl)-ethyl]-carbamic acid tert-butyl ester as a yellow solid which was further dried under HV (8.690 g; 42%). LC-MS: tR=0.88 min.; [M+H]+=505.77 g/mol.

Provenance & Evidence