Br[C:2]1[CH:10]=[CH:9][C:5]2[NH:6][CH:7]=[N:8][C:4]=2[C:3]=1[CH3:11].[CH3:12][N:13](C=O)C>[C-]#N.[C-]#N.[Zn+2].C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.Cl[Pd]Cl.[Fe+2].[Zn]>[CH3:11][C:3]1[C:4]2[N:8]=[CH:7][NH:6][C:5]=2[CH:9]=[CH:10][C:2]=1[C:12]#[N:13]A mixture of 158 (21 g; 99 mmol), Zn(CN)2 (23.2 g; 198 mmol), Pd(dppf)Cl2 (6.4 g; 9.9 mmol) and zinc (258 mg; 4 mmol) in dry DMF (150 mL) under inert atmosphere was heated at 120° C. for 2 h. The reaction mixture was filtered through a pad of Celite® that was washed with EtOAc. The organics were washed with water, dried (MgSO4), filtered and evaporated in vacuo. The crude product was purified by SiO2 chromatography eluted with a DCM/MeOH gradient (0 to 10% MeOH) to afford 8.3 g (53%) of 4-methyl-1H-benzo[d]imidazole-5-carbonitrile (160) as a brown solid: MS (ESI) m/z=158 [M+1]+.
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