Methyl iodide → (RS)-6-[2-(2-Chloro-4-methoxy-phenyl)-propionyl]-4-methyl-4H-benzo[1,4]oxazin-3-one

Participants

Reaction Steps

To a solution of 6-[2-(2-chloro-4-methoxy-phenyl)-acetyl]-4-methyl-4H-benzo[1,4]oxazin-3-one (5.9 g, 17 mmol) in tetrahydrofuran (380 ml) was added sodium hydride (60% dispersion in mineral oil, 0.72 g, 17.9 mmol). The mixture was stirred at room temperature for 1.5 h and then placed in an ice bath. A solution of methyl iodide (2.54 g, 17.9 mmol) in tetrahydrofuran (15 ml) was added dropwise (5 min). The ice bath was removed and the mixture was stirred at 35° C. for 3.5 h. The reaction mixture was poured on ice-water and extracted twice with AcOEt. The organic phases were washed with water and brine, dried (MgSO4), filtered and concentrated. The product was purified by column chromatography (SiO2, heptane/EtOAc 2:1) to give the title compound (3.3 g) as a light yellow foam. MS (m/e)=360.2 [M+H+].

Provenance & Evidence