Hydrochloric Acid → beta-Cyclocitral

54.2 Ml (0.077M) of a 1.42N solution of butyl-lithium in hexane were added at -10/+15° to a solution of 10.0 g (0.055M) of methyl beta-cyclogeranate in 150 ml of anhydrous THF. After having been left at 15° during 5 mn, there were added to the reaction mixture 15.9 ml of a 70% solution of VITRIDE in toluene (0.055M). The temperature of the mixture was then raised to 40° and, at this temperature, it was left under stirring for 45 mn. The mixture was then rapidly poured at 15° onto a solution of 20.35 g (0.275M) of 2-butanol in 100 ml of THF. At the end of the reaction, 150 ml of a 5% aqueous HCl were rapidly added and an extraction was then carried out with ether. The combined organic extracts were washed, dried over Na2SO4 and concentrated to give a residue which, on distillation in a bulb apparatus, gave 7.74 g of beta-cyclocitral (purity: 76%; yield: 70%). By carrying out the hydrolysis with a saturated aqueous solution of ammonium chloride or with aqueous HCl instead of 2-butanol, a mixture of beta-/gamma-cyclocitral was obtained the isomeric content of which was of about 70/30.

1. waitAfter having been left at 15° during 5 mn, there
2. temperatureThe temperature of the mixture was then raised to 40° and, at this temperature, it
3. waitwas left
4. additionwere rapidly added
5. extractionan extraction
6. washThe combined organic extracts were washed
7. dry with materialdried over Na2SO4
8. concentrationconcentrated
9. customto give a residue which
10. distillationon distillation in a bulb apparatus

ORD record

ord-48534df1c01b43fcb14a9e86bda5ca5f

Source dataset

uspto-grants-1989_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04868340