4-Oxazolecarboxylic acid, 5-[4-(trifluoromethyl)phenyl]-, ethyl ester → HCID 22473478, compound

Participants

Reaction Conditions

Reaction Steps

A solution of Example 52A (2.08 g, 7.29 mmol) in THF (20 mL) was cooled to −78° C. Diisobutylaluminum hydride (1.0 M in toluene, 14.6 mL, 14.6 mmol) was added slowly via syringe, and the reaction mixture was allowed to proceed 1 hr, then warmed to −20° C. After an additional 1 hr the reaction mixture was quenched with 1 N aq HCl, and the mixture was partitioned between Et2O and saturated aq NH4Cl solution. The separated aqueous phase was extracted with EtOAc, and the combined organic layer was washed with 3 N aq HCl and brine, dried (Na2SO4), filtered, and concentrated in vacuo. The crude product was purified on silica gel (Analogix® Intelliflash 280™; SF40-150 g column; 15% to 55% EtOAc/hexanes, 30 min) to give 1.26 g (72%) of the title compound as a pale yellow solid. 1H NMR (300 MHz, DMSO-d6) δ 10.07 (s, 1H), 8.75 (s, 1H), 8.30 (d, J=8.1, 2H), 7.97 (d, J=8.2, 2H). MS (DCI+) m/z 259 (M+NH4).

Provenance & Evidence