Cyclohexanone → 1,5-Dioxaspiro(5.5)undecane

To a solution of cyclohexanone (32 ml, 0.31 mol) in dry dichloromethane (950 ml) were added successively 1,3-propanediol (33.5 ml, 0.46 mol), triethyl orthoformate (51.5 ml, 0.31 mol) and zirconium chloride (1.44 g, 6.18 mmol) with stirring, and the resulting mixture was stirred at room temperature under a nitrogen atmosphere for 1 hour. After stirring, ice-chilled 1N aqueous sodium hydroxide solution (1.5 l) was added to the reaction mixture with stirring, and the resulting mixture was extracted with dichloromethane. The extract was washed with water and dried over anhydrous sodium sulfate. After filtration, the solvent was removed in vacuo, and the residue was purified by reduced-pressure distillation to afford cyclohexanone trimethylene ketal (26.8 g, yield: 55%).

1. stirringthe resulting mixture was stirred at room temperature under a nitrogen atmosphere for 1 hour
2. stirringAfter stirring
3. additionwas added to the reaction mixture
4. stirringwith stirring
5. extractionthe resulting mixture was extracted with dichloromethane
6. washThe extract was washed with water
7. dry with materialdried over anhydrous sodium sulfate
8. filtrationAfter filtration
9. customthe solvent was removed in vacuo
10. distillationthe residue was purified by reduced-pressure distillation

ORD record

ord-4a4aec95a2f34736827ecbaefffa68a5

Source dataset

uspto-grants-2009_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07638551B2