反应详情

To a stirred suspension of 3-[6-(2,4-dimethoxy-benzylamino)-3H-isobenzofuran-1-ylidene]-1,3-dihydro-indol-2-one (1 g, 2.41 mmol) and 37% formaldehyde aqueous solution (2 ml, 27 mmol) in acetonitrile (30 ml), was added sodium cyanoborohydride (606 mg, 9.64 mmol). The mixture was stirred at room temperature for 2 hours, and 10% AcOH aqueous solution (30 ml) was added. The mixture was continuously stirred for another 10 minutes. The yellow precipitate separated, washed with MeOH and dried under vacuum to give a crude product. Recrystallization of the crude product with MeOH led to 3-{6-[(2,4-dimethoxy-benzyl)-methyl-amino]-3H-isobenzofuran-1-ylidene}-1-hydroxymethyl-1,3-dihydro-indol-2-one as yellow needles (0.9 g, 82%).

1. stirringThe mixture was continuously stirred for another 10 minutes
2. customThe yellow precipitate separated
3. washwashed with MeOH
4. customdried under vacuum