Methanol → 3-[3-(4-Methyl-benzo[b]thiophen-3-ylmethyl)-2-oxo-2,3-dihydro-benzimidazol-1-yl]-hexanoic acid ethyl ester

Participants

Reaction Conditions

Reaction Steps

To a solution of 1-(4-Methyl-benzo[b]thiophen-3-ylmethyl)-1,3-dihydro-benzimidazol-2-one (50 mg, 0.17 mmol) in dry DMF (1.0 mL) are added (E)-Hex-2-enoic acid ethyl ester (27 mg, 0.19 mmol) and 40% benzyltrimethyl ammonium hydroxide in MeOH (0.008 mL, 0.017 mmol). The resulting mixture is warmed up to 60° C. for 16 hr. Then another 27 mg of (E)-Hex-2-enoic acid ethyl ester is added the heating is continued for another 8 hr. Then saturated NH4Cl (2 mL) and water (10 mL) are added and the mixture is extracted with EtOAc (3×25 mL). The organic layers are combined, dried over MgSO4 and concentrated to give the crude product. Purification with flash column chromatography using 20% EtOAc in Hexanes affords 70 mg (95%) of 3-[3-(4-Methyl-benzo[b]thiophen-3-ylmethyl)-2-oxo-2,3-dihydro-benzimidazol-1-yl]-hexanoic acid ethyl ester.

Provenance & Evidence