1-(2-Trimethylsilylethoxymethyl)-2-hydroxymethylbenzimidazole → 1-(2-Trimethylsilylethoxymethyl)-2-formyl-benzimidazole

Beteiligte Stoffe

Reaktionsschritte

To a stirred solution of the alcohol from above (26.58 g, 0.096 mol) in dry CH2Cl2 (450 mL) was added activated MnO2 (<5 micron, ˜85%, 93 g, 0.91 mol) and the suspension stirred at room temperature overnight. The mixture was filtered through celite© (175 g) and the cake was washed with CH2Cl2. The solvent was removed from the eluent under reduced pressure and the resultant residue purified by column chromatography on silica gel (3% MeOH/CH2Cl2) to provide the title aldehyde (14.41 g, 55%) as a pale yellow oil. 1H NMR (CDCl3) δ −0.07 (s, 9H), 0.90 (t, 2H, J=9 Hz), 3.56 (t, 2H, J=9 Hz), 6.04 (s, 2H), 7.43-7.51 (m, 2H), 7.66 (d, 1H, J=9 Hz), 7.95 (d, 1H, J=9 Hz), 10.13 (s, 1H); 13C NMR (CD3OD) δ −1.19, 17.94, 66.62, 73.30, 112.22, 122.51, 124.64, 127.43, 136.62, 143.11, 146.39, 185.10; ES-MS m/z (M+H);

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