[F:1][C:2]1[CH:3]=[C:4]([CH:7]=[C:8]([F:11])[C:9]=1[OH:10])[C:5]#[N:6].C([O-])([O-])=O.[K+].[K+].[Br:18][CH2:19][CH2:20]Br>CN(C=O)C>[Br:18][CH2:19][CH2:20][O:10][C:9]1[C:2]([F:1])=[CH:3][C:4]([C:5]#[N:6])=[CH:7][C:8]=1[F:11]A suspension of 3,5-difluoro-4-hydroxybenzonitrile (10 g, 0.0649 mol; see Preparation B(iv) above), anhydrous K2CO3 (17.94 g, 0.1298 mol) and 1,2-dibromoethane (73.2 g, 0.389 mol) in dry DMF (100 mL) was stirred at 60° C. overnight under a nitrogen atmosphere. The reaction mixture was filtered through Celite® and the solvent was then evaporated under reduced pressure. The residue was purified by column chromatography over silica gel, using 1.5% ethyl acetate in petroleum ether as eluent, to yield 12 g of the sub-title compound as a white solid.
読み込み中…
