Cinnamoylbenzene → Dihydrochalcone

Participants

Reaction Steps

Chalcone (compound 1) (37.6 mmol) was dissolved in 250 ml of toluene (in some cases 25 ml of MeOH was added to insure a complete dissolution) and 400 mg of 10% Pd/C (0.01 eq) was added to the mixture. The compound was hydrogenated at 45 psi in a Parr apparatus for 40 min to 3 hrs to form 1,3-diphenylpropan-1-one (compound 2), during which time the reaction mixture was periodically checked for the starting material by TLC (Hex:EtOAc=1:1) to prevent over-reduction. Upon completion of reduction the reaction mixture was filtered through a short pad (2-3 inch) of silica gel and solvent was removed in vacuo to afford a crude product, which was either sufficiently pure to use in the next step or was purified by recrystallization from MeOH or Hex:EtOAc=3:1 or, in the case where over-reduction has occurred, by silica gel column chromatography using Hex:EtOAc=5:1 as an eluent.

Provenance & Evidence