1-benzofuran-4-yl trifluoromethanesulfonate

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Trifluoro-methanesulfonic acid benzofuran-4-yl ester was converted to 4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-benzofuran using conditions described in Wang, Y.-C. and Georghiou, P. E., Org. Lett. 4: 2675-78 (2002). The Suzuki coupling of 4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-benzofuran to [3-bromo-5-(2-methoxy-pyridine-4-carbonyl)-phenyl]-carbamic acid methyl ester was carried out as described in Example 75 to give [3-benzofuran-4-yl-5-(2-methoxy-pyridine-4-carbonyl)-phenyl]-carbamic acid methyl ester. 1H NMR (400 MHz, CDCl3): δ 9.08 (s, 1H), 8.38 (dd, J=5.2, 0.5 Hz, 1H), 8.29 (t, J=1.6 Hz, 1H), 8.06 (t, J=1.7 Hz, 1H), 7.96 (d, J=2.1 Hz, 1H), 7.75 (t, J=1.6 Hz, 1H), 7.62-7.56 (m, 1H), 7.48-7.42 (m, 2H), 7.29 (dd, J=5.2, 1.3 Hz, 1H), 7.15 (dd, J=2.1, 1.0 Hz, 1H), 7.08 (s, 1H), 3.96 (s, 3H), 3.75 (s, 3H).

Conditions: temp:85.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 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). 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 dried over magnesium sulfate The solvent was evaporated in vacuo the residue was purified by column chromatography on silica gel eluting with toluene The fractions containing the desired products were collected evaporated in vacuo