Diisopropylamine → HCID 58552827, compound

Participants

Reaction Conditions

Reaction Steps

n-BuLi (4.4 mL, 2.5 M in hexanes, 11.0 mmol) was added to a solution of diisopropylamine (1.57 mL, 11.2 mmol) in THF (30 mL) at −78° C. After stirring for 20 min, EtOAc (1.09 mL, 11.2 mmol) was added. The solution was stirred at −78° C. for 10 min, warmed to 0° C., stirred for 10 min, then cooled back to −78° C. A solution of 4-oxo-2-(3-(trifluoromethyl)phenyl)-4H-benzo[d][1,3]oxazine-8-carboxylate 42 (2.00 g, 5.72 mmol) in THF (50 mL) was added over 5 min to the reaction mixture and stirring at −78° C. continued for 1 h. The reaction mixture was then allowed to warm to room temperature over 2 h. MeOH (50 mL) was added followed by solid NaOMe (1.62 g, 30 mmol), and the reaction stirred vigorously for 12 h at room temperature. The solution was concentrated to 20 mL total volume in vacuo, H2O (100 mL) was added, and the mixture was extracted with ethyl acetate (2×100 mL). The combined organic layers were dried (MgSO4) and concentrated in vacuo. The crude residue was purified by MPLC eluting with pentane/EtOAc (10-50%) to give 43 (950 mg, 39% yield).

Provenance & Evidence