3-Phenylprop-2-Enal → 1-(2-Benzyloxyphenyl)-4-phenylbutadiene

Beteiligte Stoffe

Reaktionsschritte

5.28 g of cinnamaldehyde and 19.8 g of 2-benzyloxybenzyltriphenylphosphonium chloride (prepared as described in Preparation 1) were dissolved, with heating, in 200 ml of acetonitrile, and then 6 g of 1,8-diazabicyclo[5,4,0]undec-7-ene were added dropwise to the solution. The resulting mixture was then heated under reflux for 3 hours. At the end of this time, the solvent was removed by distillation under reduced pressure, and the resulting residue was partitioned between ethyl acetate and water. The organic layer was dried over anhydrous magnesium sulfate, and concentrated by evaporation under reduced pressure. The oily residue thus obtained was again dissolved in 200 ml of ethyl acetate, with heating, and 50 ml of hexane was added to the solution, after which deposited insoluble materials were filtered off. The filtrate was concentrated by evaporation under reduced pressure, and the resulting residue was purified by column chromatography through silica gel, using a 9:1 by volume mixture of hexane and ethyl acetate as the eluent, to give 12.2 g (yield 97.7%) of 1-(2-benzyloxyphenyl)-4-phenylbutadiene as a colorless oil.

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