Potassium Carbonate → 4-Ethyl-5-[4-(trifluoromethyl)phenyl]oxazole

Participants

Reaction Steps

A mixture of 4-(trifluoromethyl)benzaldehyde (3.60 mL, 27.0 mmol), 1-(1-isocyanopropylsulfonyl)-4-methylbenzene (6.02 g, 27.0 mmol), and K2CO3 (4.47 g, 32.4 mmol) in MeOH (100 mL) was heated to reflux. After 1.5 hr the reaction mixture was cooled to ambient temperature, and the volatiles evaporated at reduced pressure. The residue was partitioned between Et2O (100 mL) and H2O (100 mL). The separated aqueous phase was extracted with Et2O. The combined organic extract was washed with brine, dried (MgSO4), filtered, and concentrated in vacuo. Chromatography on silica gel (Analogix® Intelliflash 280™; SF40-150 g column; 10% to 30% EtOAc/hexanes eluant, 30 min) afforded 5.75 g (88%) of the title compound as a pale yellow oil. 1H NMR (300 MHz, DMSO-d6) δ 8.44 (s, 1H), 7.90-7.78 (m, 4H), 2.79 (q, J=7.5, 2H), 1.23 (t, J=7.5, 3H). MS (DCI+) m/z 242 (M+H).

Provenance & Evidence