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

Participants

Reaction Conditions

Reaction Steps

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).

Provenance & Evidence