A mixture of CH3CN (0.62 mL, 11.84 mmol), DMSO (2 mL) and NaH (410 mg, 10.26 mmol) was stirred for 45 minutes at room temperature before a solution of methyl 1-methyl-1H-benzo[d]imidazole-6-carboxylate and methyl 1-methyl-1H-benzo[d]imidazole-5-carboxylate (1.5 g, 7.89 mmol) in CH3CN (5 mL) was added dropwise. The resulting mixture was stirred at room temperature for 2 h before quenching by the addition of saturated NH4Cl and extraction with DCM (3×30 ml). The combined organic layers were concentrated to give the desired products 3-(1-methyl-1H-benzo[d]imidazol-6-yl)-3-oxopropanenitrile and 3-(1-methyl-1H-benzo[d]imidazol-5-yl)-3-oxopropanenitrile (600 mg, 38%) and used in the next step without further purification. LCMS (m/z): 200.07 (M+1).
