Potassium Carbonate → HCID 57785964, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of ethyl 4-[2-[(2,4-dimethoxyphenyl)amino]-7-(1-ethylpropyl)-1H-benzimidazol-1-yl]butanoate (Reference Example 56; 569.3 mg, 1.26 mmol) in tetrahydrofuran (5.0 mL) was added lithium borohydride (82.0 mg, 3.77 mmol) at 0° C. The reaction mixture was stirred at 60° C. for 1.5 hr. After cooling, the reaction mixture was quenched with water at 0° C. and extracted with ethyl acetate (×3). The combined organic layer was washed with brine, dried over anhydrous magnesium sulfate, filtered and concentrated in vacuo. The resulting crude butanol (MS Calcd.: 411; Found: 412 (M+H)) was subjected for the next step without further purification. To a solution of the crude material in pyridine (1.0 mL) was added methanesulfonyl chloride (490 μL, 6.28 mmol) at 0° C. The reaction mixture was stirred at room temperature for 2 hr. The reaction mixture was quenched with aqueous sodium hydrogen carbonate and extracted with ethyl acetate (×3). The combined organic layer was washed with brine, dried over anhydrous magnesium sulfate, filtered and concentrated in vacuo. The crude mesylate was subjected for the next step without further purification. To the crude material (MS Calcd.: 489; Found: 490 (M+H)) in NAN-dimethylformamide (1.0 mL) was added potassium carbonate (346.9 mg, 2.51 mmol). The reaction mixture was stirred at 60° C. for 19 hr. After cooling, the reaction mixture was diluted with water and extracted with ethyl acetate (×3). The combined organic layer was washed with water (×2) and brine, dried over anhydrous magnesium sulfate, filtered and concentrated in vacuo. The residue was purified by silica gel column chromatography eluting with a 10-40% ethyl acetate/n-hexane gradient mixture. The resulting solid was washed with n-hexane to give the title compound as a colorless powder (144.5 mg, 0.367 mmol, 29%).

Provenance & Evidence