Hydrochloric Acid → 6-[2-(2-chloro-5-methoxy-phenyl)-acetyl]-4-methyl-4H-benzo[1,4]oxazin-3-one

To a solution of (2-chloro-5-methoxy-phenyl)-acetic acid (1 g) in tetrahydrofuran (20 ml) were added N,N-dimethylformamide (2 drops) and oxalylchloride (1.03 g). The mixture was stirred overnight at room temperature. The solvent was evaporated; toluene was added and again evaporated. The residue was dried under high vacuum to give the crude acid chloride. To a cooled solution (ice bath) of 4-methyl-2H-1,4-benzoxazin-3(4H)-one (830 mg) in 1,2-dichloroethane (5 ml) was added AlCl3 (1.99 g). The mixture was stirred for 10 min and a solution of the acid chloride in 1,2-dichloroethane (5 ml) was added dropwise. The mixture was stirred at 0° C. for 4.5 h. The mixture was poured into ice water and hydrochloric acid and extracted with dichloromethane. The organic phase was dried (MgSO4), filtered and concentrated. The product was purified by chromatography (SiO2, cyclohexane/EtOAc 1:0=>0:1) to give the title compound (1.6 g) as an off-white solid. MS (m/e)=346.1 [M+H+].

1. customThe solvent was evaporated
2. additiontoluene was added
3. customagain evaporated
4. customThe residue was dried under high vacuum
5. customto give the crude acid chloride
6. stirringThe mixture was stirred for 10 min
7. stirringThe mixture was stirred at 0° C. for 4.5 h
8. extractionextracted with dichloromethane
9. dry with materialThe organic phase was dried (MgSO4)
10. filtrationfiltered
11. concentrationconcentrated
12. customThe product was purified by chromatography (SiO2, cyclohexane/EtOAc 1:0=>0:1)

ORD record

ord-8342743b08eb44c9a68b0c0564aadc66

Source dataset

uspto-grants-2012_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08268820B2