1,5-Diazabicyclo(4.3.0)non-5-ene → 1-(3-Butenyl)-1,4,5,6,7,8-Hexahydroanthraquinone

Participants

Reaction Steps

A mixture of 13.8 g of tetrahydronaphthoquinone (0.085 mole) and 10 g (0.092.5 mole) of 1,3,7-octatriene was refluxed for 11/2 hours in 100 ml of ethanol. After the addition of 1 ml of 1,5-diazabicyclo[4.3.0]non-5-ene (DBN), the mixture was stirred while exposed to air for 24 hours. The ethanol was then blown off and the residue was dissolved in benzene and chromatographed on acidic alumina. From the eluate, 11.2 g of crude product were obtained (49% yield). The crude product was rechromatographed on acidic alumina using a 3:1 mixture of cyclohexane/benzene as the eluent. After removal of the solvent, the product was recrystallized from methanol to yield an analytical product having a mp of 47° to 48° C.

Provenance & Evidence