反应详情

A solution of methyl 5-formyl-2-thiophenecarboxylate, prepared according to Example 10, (6.26 g, 36.78 mmoles), hydroxylamine hydrochloride (3.07 g, 44.14 mmoles) and pyridine (3.49 g, 44.14 mmoles) in 200 ml of ethanol was refluxed for 2 hours. The ethanol was removed in vacuo, the residue dissolved in ether and washed with water. The organic layer was dried (magnesium sulfate) and evaporated to a yellow solid. Trituration with a small amount of ether furnished the title compound as a white solid (4.93 g, 72%), m.p. 164°-7° C. Oxime Z:E ratio:(82:18).

1. temperaturewas refluxed for 2 hours
2. customThe ethanol was removed in vacuo
3. dissolutionthe residue dissolved in ether
4. washwashed with water
5. dry with materialThe organic layer was dried (magnesium sulfate)
6. customevaporated to a yellow solid