1,8-Diazabicyclo(5.4.0)undec-7-ene → HCID 15544964, compound

Temperature

-30 °C

The acetoxy cyclopentanone 1 (approx. 28.5 mmol) in ether (40 ml) was added dropwise over 1 hr to a stirred solution of DBU (4.27 ml, 28.5 mmol) in ether (50 ml) at −40° C. under argon. The mixture was allowed to warm to −30° C. and stirred for 30 minutes before being quenched with dilute hydrochloric acid (20 ml). The reaction mixture was partitioned between ether (100 ml) and 1N HCl (150 ml). The organic layer was separated and the aqueous layer was further extracted with ether (2×100 ml). The combined ether layers were washed with brine, dried (MgSO4) and the solvent was evaporated under reduced pressure. The residue was chromatographed (SiO2, pentane-ether, 1:0 to 8:2) to give the propylcyclopentenone 2 (2.4 g, 68% from (R)-4-acetoxycyclopent-2-enone). νmax(film)/cm−1 1708 (C═O).

1. custombefore being quenched with dilute hydrochloric acid (20 ml)
2. customThe reaction mixture was partitioned between ether (100 ml) and 1N HCl (150 ml)
3. customThe organic layer was separated
4. extractionthe aqueous layer was further extracted with ether (2×100 ml)
5. washThe combined ether layers were washed with brine
6. dry with materialdried (MgSO4)
7. customthe solvent was evaporated under reduced pressure
8. customThe residue was chromatographed (SiO2, pentane-ether, 1:0 to 8:2)

ORD record

ord-cab0160828924c0794eb758c46c4bc0c

Source dataset

uspto-grants-2005_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06872856B2