反应详情

The mixture of 10 g of 2-(1,4-benzodioxan-2-yl)-oxiran [Tetrahedron 18, 289 (1962)], 2 g of potassium cyanide, 2 g of ammonium chloride and 25 ml of dimethylformamide is stirred at room temperature for 3 days. The mixture is diluted with water and extracted with methylene chloride. The extract is evaporated and the residue dehydrated by refluxing in a mixture of 11 ml of acetic acid, 11 ml of water and 4 ml of sulfuric acid for 24 hours. The mixture is diluted with ice, extracted with diethyl ether and the extract evaporated to yield the 3-(1,4-benzodioxan-2-yl)-acrylic acid. The solution of 5 g thereof in 25 ml of tetrahydrofuran is treated with 5.5 g of carbonyldiimidazole and the mixture, stirred for 30 minutes. Then the solution of 4.6 g of 1-(4-piperidyl)-2-imidazolidinone in 25 ml of iospropanol is added and the mixture allowed to stand overnight. It is evaporated, the residue taken up in ethyl acetate, the solution washed successively with water, diluted aqueous sodium hydroxide and water and evaporated. The residue is dissolved in 100 ml of tetrahydrofuran, cooled in an ice bath and treated dropwise with 20 ml of a 1.2 molar solution of alane triethylamine complex while stirring. After 5 hours, the cold mixture is treated dropwise with 10 ml of 25% aqueous sodium hydroxide, the organic solvent phase is decanted from the pasty slurry of inorganic salts and evaporated to give the 1-[1-[3-(1,4-benzodioxan-2-yl)-2-propenyl]-4-piperidyl]-2-imidazolidinone.

1. extractionextracted with methylene chloride
2. customThe extract is evaporated
3. temperatureby refluxing in a mixture of 11 ml of acetic acid, 11 ml of water and 4 ml of sulfuric acid for 24 hours
4. additionThe mixture is diluted with ice
5. extractionextracted with diethyl ether
6. customthe extract evaporated