反应详情

A mixture of 2-(7-hydroxyheptyl)-3-oxocyclopentanecarbonitrile (20 g.), ethylene glycol (5.6 g.), p-toluenesulphonic acid (1 g.) and benzene (160 ml.) was heated to reflux for 31/2 hours with continuous removal of water. The mixture was cooled to ambient temperature, anhydrous sodium carbonate was added, and after filtration through a bed of sodium carbonate, the solvent was removed under reduced pressure. The residue was distilled under reduced pressure to give 7-cyano-6-(7-hydroxyheptyl)-1,4-dioxaspiro[4,4]nonane (19.3 g.), b.p. 166°-182° C./0.1 mm.Hg. This material was used as a starting material in the next stage, an aliquot being redistilled to b.p. 177°-179° C./0.1 mm.Hg for elemental analysis:

1. temperaturewas heated
2. temperatureto reflux for 31/2 hours
3. customwith continuous removal of water
4. additionanhydrous sodium carbonate was added
5. filtrationafter filtration through a bed of sodium carbonate
6. customthe solvent was removed under reduced pressure
7. distillationThe residue was distilled under reduced pressure