[CH3:1][C:2]1[C:10]2[N:9]=[CH:8][NH:7][C:6]=2[CH:5]=[CH:4][C:3]=1[C:11]#[N:12].C1COCC1.[O:18]1[CH:23]=[CH:22][CH2:21][CH2:20][CH2:19]1.CC1C=CC(S(O)(=O)=O)=CC=1.O>CCOC(C)=O>[CH3:1][C:2]1[C:10]2[N:9]=[CH:8][N:7]([CH:19]3[CH2:20][CH2:21][CH2:22][CH2:23][O:18]3)[C:6]=2[CH:5]=[CH:4][C:3]=1[C:11]#[N:12]
To a stirred solution of 160 (8.3 g, 52.5 mmol) and THF (100 mL) at RT under nitrogen was added, 3,4-dihydro-2H-pyran (35 g, 420 mmol) and p-TsOH.H2O (0.9 g, 5.3 mmol) and the reaction mixture was heated at 75° C. for 4 h. The mixture was cooled to RT, diluted with EtOAc and sequentially washed with sat'd. aq. NaHCO3, and brine. The organic extract was dried (Na2SO4), filtered and concentrated in vacuo. The crude product was purified by SiO2 chromatography eluting with a MeOH/DCM gradient (0 to 5% MeOH) to afford 9.8 g (77%) of 4-methyl-1-(tetrahydro-2H-pyran-2-yl)-1H-benzo[d]imidazole-5-carbonitrile (162) as a light yellow solid: MS (ESI) m/z=242 [M+1]+.
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