Sodium hydride → 2-[3-(tert-Butoxycarbonyl-phenethyl-amino)-propylsulfanyl]-benzoimidazole

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Reaction Steps

Phenethyl-carbamic acid tert-butyl ester (1107 mg, 5.0 mmol) is dissolved in dry DMF (7.75 ml). To this solution, sodium hydride (60% w/w in oil, 302 mg, 7.55 mmol) is added under vigorous stirring and stirring is continued for 30 min. Then 1-chloro-3-iodo-propane (250 mg, 5.0 mmol) is dropped into the solution followed by stirring for 2 h at rt and another hour at 50° C. After switching off the heating and addition of sodium 1H-benzoimidazole-2-thiolate (1722 mg, 10 mmol) the mixture is allowed to stir overnight at rt. All the DMF is evaporated in vacuo and the remaining crude is dissolved in DCE. This organic phase is washed twice with water, dried over Na2SO4 and evaporated to give the crude product which is purified by flash chromatography on silica gel (AcOEt/heptane, 1:9 to 1:1), yielding the title compound (289 mg) in 14% as a colourless oil: tR=2.24 min (LC-2), ESI-MS (pos.): m/z 412.43 [M+H]+, MS (neg.): m/z 410.46 [M−H]+; 1H-NMR (CDCl3): δ (ppm) 1.48 (s, 9H, tBu), 1.89 (br. s, 2H, SCH2CH2), 2.83 (t, 2H, PhCH2CH2N), 3.09 (br. s, 2H), 3.26 (br. s, 1H), 3.42 (t, 2H, PhCH2CH2N), 3.47 (br. s, 2H), 7.13-7.30 (m, 7Harom), 7.52 (m, 2H).

Provenance & Evidence