反应详情

温度

65 °C

Acetamidoxime hydrochloride (1.5 g) was added portionwise to an ice-cooled suspension of sodium hydride (1.18 g of a 60% dispersion in oil) in dry tetrahydrofuran (40 ml) under an atmosphere of argon. Molecular sieve type 4A (8-12 mesh) were added followed by a solution of ethyl 4-iodobenzoate (3.73 g) in tetrahydrofuran (10 ml). The mixture was heated at 65° C. for 3 hours. The mixture was cooled to ambient temperature and partitioned between ethyl acetate and water. The organic extract was separated, washed with saturated brine, dried (MgSO4) and evaporated. The residue was purified by flash column chromatgraphy on silica gel using a 70:30 (v/v) mixture of ethyl acetate/hexane as eluent to give 3-methyl-5-(4-iodophenyl)-1,2,4-oxadiazole as a solid (1.12 g), m.p. 136°-7° C.; microanalysis, found: C, 38.2; H, 2.5; H, 9.5%; C9H7IN2O requires: C, 37.8; H, 2.47; N, 9.79%; NMR: 2.41(3H,s), 7.84(2H,d) and 8.02(2H,d); m/z 287(M+H).

1. temperaturecooled
2. temperatureThe mixture was cooled to ambient temperature
3. custompartitioned between ethyl acetate and water
4. extractionThe organic extract
5. customwas separated
6. washwashed with saturated brine
7. dry with materialdried (MgSO4)
8. customevaporated
9. customThe residue was purified by flash column chromatgraphy on silica gel using
10. additiona 70:30 (v/v) mixture of ethyl acetate/hexane as eluent