FC(F)(F)S(O[C:7]1[C:12]2[CH:13]=[CH:14][O:15][C:11]=2[CH:10]=[CH:9][CH:8]=1)(=O)=O.[CH3:18][C:19]1([CH3:33])[CH2:23][O:22][C:21]([C:24]2[CH:25]=[C:26](B(O)O)[CH:27]=[CH:28][CH:29]=2)=[N:20]1.C(N(CC)CC)C>CN(C)C=O>[O:15]1[C:11]2[CH:10]=[CH:9][CH:8]=[C:7]([C:26]3[CH:25]=[C:24]([C:21]4[O:22][CH2:23][C:19]([CH3:33])([CH3:18])[N:20]=4)[CH:29]=[CH:28][CH:27]=3)[C:12]=2[CH:13]=[CH:14]1A mixture of 4-trifluoromethylsulfonyloxy-benzofuran (2 g), 3-(4,4-dimethyl-4,5-dihydrooxazol-2-yl)phenyldihydroxyborane (2.14 g), tetrakis(triphenyl-phosphine)palladium(0) (0.26 g) and triethylamine (2.28 g) in N,N-dimethylformamide (40 ml) was heated at 85° C. for 3 hours under nitrogen atmosphere. After evaporating the solvent, the residue was dissolved in a mixture of ethyl acetate (100 ml) and water (100 ml). The organic layer was successively washed with 10% sodium carbonate aqueous solution, brine and dried over magnesium sulfate. The solvent was evaporated in vacuo and the residue was purified by column chromatography on silica gel eluting with toluene. The fractions containing the desired products were collected and evaporated in vacuo to afford 2-[3-(benzofuran-4-yl)phenyl]-4,4-dimethyl-4,5-dihydrooxazole (1.52 g).
Loading…