反应详情

N-(3-Benzyloxyoctyl)-4,4-ethylenedioxycyclopent-2-enamine (972 mg) in ethanol (60 ml) was treated with potassium cyanate (360 mg) in water (4.0 ml) then 1.0N aqueous hydrochloric acid (3.0 ml) at room temperature. After 18 hours, the mixture was diluted with water and extracted with chloroform. The extract was dried then decolourised and the solvent was removed in vacuo to give crude N-(3-benzyloxyoctyl)-N-(4,4-ethylenedioxycyclopent-2-enyl)urea as a yellow glass. This material was dissolved in tetrahydrofuran (11.0 ml) and 2.0N aqueous hydrochloric acid (11.0 ml) and the solution set aside at room temperature for 1.25 hours. After dilution with water, the product was extracted into chloroform, and the solvent removed from the dried extract to give the mixture of diastereomers of 2-(3-benzyloxyoctyl)-cis-2,4-diazabicyclo[3.3.0]octane-3,7-dione as a colourless glass, δ (CDCl3) 0.95 (3H, bt, --CH3), 2.41 (4H, m, ##STR13## 3.40 (2H, m, --N--CH2 --), 4.24 (2H, m, 1-H, 5-H), 4.48 and 4.50 (total 2H, both s, --CH2Ph from each isomer), 7.31 (5H, bs, --Ph).

1. customat room temperature
2. extractionextracted with chloroform
3. customThe extract was dried
4. customthe solvent was removed in vacuo