Potassium Fluoride → 2-(4-{2-[2-(2'-Methoxy-biphenyl-4-yl)-5-methyloxazol-4-yl]-ethoxy}-phenoxy)-2-methylpropionic acid ethyl ester

Participants

Reaction Steps

A solution of 2-(4-{2-[2-(4-bromophenyl)-5-methyloxazol-4-yl]ethoxy}phenoxy)-2-methylpropionic acid ethyl ester (300 mg, 0.614 mmol) (see Ex. 2, part B), o-methoxyphenylboronic acid (140 mg, 0.921 mmol), potassium fluoride (88.6 mg, 1.84 mmol), palladium acetate (1.3 mg, 0.14 μmol), and 2-(dicyclohexylphosphino)biphenyl (4.3 mg, 12.3 μmol) were combined under N2, to which anhydrous THF (1.23 mL) was added. The yellow mixture was heated at reflux for 12 h. After cooling to room temperature, the mixture was partitioned between Et2O (20 mL) and 1M NaOH (10 mL). The layers were separated, and the aqueous phase was back-extracted with Et2O (10 mL). Combined organic phases were dried over Na2SO4, and concentrated. The product was purified by silica gel chromatography (25 g SiO2, 1:4 ethyl acetate:hexanes) to yield 100.5 mg (32%) as an oil. Rf=0.38 in 1:4 ethyl acetate:hexanes; 1H NMR (400 MHz, CDCl3) δ7.97 (d, J=8.0 Hz, 2H), 7.57 (d, J=8.0 Hz, 2H), 7.33-7.29 (m, 2H), 7.01 (t, J=7.2 Hz, 1H), 6.97 (d, J=7.6 Hz, 1H), 6.80-6.74 (m, 4H), 4.20 (q, J=7.2 Hz, 2H), 4.17 (t, J=6.8 Hz, 2H), 3.80 (s, 3H), 2.94 (t, J=6.8 Hz, 2H), 2.34 (s, 3H), 1.50 (s, 6H), 1.24 (t, J=7.2 Hz, 3H); MS (EI) 538.2 (M+Na)+, 516.2 (M+H)+.

Provenance & Evidence