Br[C:2]1[CH:9]=[CH:8][C:5]([CH:6]=[O:7])=[CH:4][CH:3]=1.[S:10]1[CH:14]=[CH:13][CH:12]=[C:11]1B(O)O.C([O-])([O-])=O.[Na+].[Na+]>COCCOC.C1COCC1.C1C=CC([P]([Pd]([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)[P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1>[S:10]1[CH:14]=[CH:13][CH:12]=[C:11]1[C:2]1[CH:9]=[CH:8][C:5]([CH:6]=[O:7])=[CH:4][CH:3]=1
To a stirred degassed solution of 4-bromobenzaldehyde (371 mg, 2.00 mmol) and thiophene-2-boronic acid (287 mg, 2.24 mmol) in DME/THF (5 mL, 4:1) were added a 2 M Na2CO3 solution (3.0 mL) and Pd(PPh3)4 (110 mg, 0.095 mmol). The reaction mixture was flushed with argon and maintained under argon while being heated at 85° C. over 2 days. The mixture was then cooled and diluted with EtOAc (35 mL) and water (30 mL). The aqueous layer was washed with EtOAc (2×10 mL) and the combined organic extracts dried (Na2SO4), filtered and concentrated. Purification of the resultant oil by column chromatography on silica gel (Hexanes/EtOAc, 4:1) afforded the title compound (293 mg, 78%) as a yellow solid. 1H NMR (CDCl3) δ 7.14 (dd, 1H, J=5.1, 3.6 Hz), 7.40 (dd, 1H, J=5.1, 0.9 Hz), 7.46 (dd, 1H, J=3.6, 0.9 Hz), 7.76 (d, 2H, J=8.4 Hz), 7.88 (d, 2H, J=8.4 Hz), 10.00 (s, 1H).
Wird geladen…
