反应详情

Oxalyl chloride (0.156 ml) and N,N-dimethylformamide (catalytic amount) were added to a solution of E-4-[4-(5-methyl-2-phenyl-4-oxazolylmethoxy)benzyloxyimino]-4-phenylbutyric acid (700 mg) in tetrahydrofuran (10 ml) at room temperature, which was stirred at room temperature for 30 minutes and concentrated. The residue was dissolved in tetrahydrofuran (5 ml) and added dropwise to a mixture of a 40% aqueous methylamine (20 ml) and ethyl acetate (30 ml) at 0° C. After stirred at room temperature for 1 hour, water was added and extracted with ethyl acetate. The ethyl acetate layer was washed with an aqueous saturated solution of sodium chloride, dried (MgSO4) and concentrated. The remaining crystals were recrystallized from ethyl acetate-hexane to obtain E-N-methyl-4-[4-(5-methyl-2-phenyl-4-oxazolylmethoxy)benzyloxyimino]-4-phenylbutaneamide (466 mg, yield 65%) as colorless crystals. m.p. 141-142° C.

1. concentrationconcentrated
2. dissolutionThe residue was dissolved in tetrahydrofuran (5 ml)
3. additionadded dropwise to a mixture of a 40% aqueous methylamine (20 ml) and ethyl acetate (30 ml) at 0° C
4. stirringAfter stirred at room temperature for 1 hour
5. additionwater was added
6. extractionextracted with ethyl acetate
7. washThe ethyl acetate layer was washed with an aqueous saturated solution of sodium chloride
8. dry with materialdried (MgSO4)
9. concentrationconcentrated
10. customThe remaining crystals were recrystallized from ethyl acetate-hexane