Triethylamine → Ethyl 5-(4-(trifluoromethyl)phenyl)-4,5-dihydroisoxazole-3-carboxylate

Participants

Reaction Steps

To a mixture of 1-(trifluoromethyl)-4-vinylbenzene (2.0 g, 11.27 mmol), a compound of formula (20) and ethyl 2-chloro-2-(hydroxyamino)acetate (2.11 g, 13.52 mmol), a compound of formula (21), in anhydrous THF was added a solution of triethylamine (3.0 ml) in tetrahydrofuran was added dropwise at room temperature. The mixture was stirred overnight under N2. The white precipitate thus formed was filtered off, and washed twice with tetrahydrofuran (10 ml). The solvent was removed from the filtrate under reduced pressure, and the residue partitioned between water/ethyl acetate (20 ml:20 ml v/v), extracting three times with 20 ml of ethyl acetate. The combined organic layers were washed with aqueous ammonium chloride, and dried over MgSO4, to provide ethyl 5-[4-(trifluoromethyl)phenyl]-4,5-dihydroisoxazole-3-carboxylate, a compound of formula (22).

Provenance & Evidence