Hydrochloric Acid → Spiro[bicyclo[2.2.1]heptane-2,1'-cyclopropane]-3-carbaldehyde

Temperatur

0 °C

Methoxymethyltriphenylphosphonium chloride (6.41 g) was suspended in tetrahydrofuran (80 mL) and cooled to 0° C. in nitrogen atmosphere. After adding 1.56 M n-butyl lithium-in-hexane solution (36.2 mL) at 0° C., the reaction mixture was stirred for an hour. Into the resulting deep red-colored solution, a spiro[bicyclo[2.2.1]heptane-2,1′-cyclopropane]-3-one (6.41 g) solution in tetrahydrofuran (10 mL) was dropped at 0° C., and thereafter the temperature was raised to room temperature, followed by an overnight's stirring. To the reaction mixture, 5M hydrochloric acid (50 mL) was added at room temperature and stirred for further 3 hours. The reaction mixture was diluted with water and extracted with diethyl ether. The extract washed with saturated brine, dried over anhydrous sodium sulfate, the solvent was removed by distillation and the resulting residue was purified on silica gel column chromatography (hexane/ethyl acetate=99/1−97/3) to provide 5.04 g of the title compound as a colorless oily substance.

1. temperaturethe temperature was raised to room temperature
2. stirring's stirring
3. stirringstirred for further 3 hours
4. extractionextracted with diethyl ether
5. washThe extract washed with saturated brine
6. dry with materialdried over anhydrous sodium sulfate
7. customthe solvent was removed by distillation
8. customthe resulting residue was purified on silica gel column chromatography (hexane/ethyl acetate=99/1−97/3)

ORD-Eintrag

ord-a366e3c4b4a343169fd9d90f48350a68

Quelldatensatz

uspto-grants-2007_11

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07300947B2