反应详情

Hydroxylamine hydrochloride (0.29 g), then pyridine (7.7 ml), was added under nitrogen to a stirred solution of diethyl 3-oxo-3(1-trityl-1,2,4-triazol-3-yl)propane phosphonate (1.0 g, prepared as described in Example 42) in ethanol (20 ml). The mixture was stirred at room temperature for three hours, then evaporated under reduced pressure. The residue was treated with water, basified to pH 8 with 1M sodium hydroxide solution, and extracted with chloroform. The organic layers were washed with brine, dried over magnesium sulphate and evaporated under reduced pressure. The residue was chromatographed on silica, using dichloromethane-ethanol (19:1) as eluant, to give diethyl 3-oximino-3(1-trityl-1,2,4-triazol-3-yl)propane phosphonate (0.90 g, m.p. 190°-192° C.), probably as a single geometric isomer of unknown configuration. NMR (CDCl3): δ1.2(6H,t), 1.95-2.1(2H,m), 3.05(2H,m), 3.95(4H,m), 7.1-7.3(15H,m), 8.0(1H,s), 9.1(1H,br).

1. customevaporated under reduced pressure
2. additionThe residue was treated with water
3. extractionextracted with chloroform
4. washThe organic layers were washed with brine
5. dry with materialdried over magnesium sulphate
6. customevaporated under reduced pressure
7. customThe residue was chromatographed on silica