Question

Can you make a seperation scheme for this Tetraphenylcyclopentadienone lab ? Please use the procedure below to make it. Thank you.

Procedure:

Add 1.5 g benzil, 1.5 g dibenzyl ketone, and 12 mL absolute ethanol to a 50-mL round-bottom flask. Place a magnetic stir bar in the flask. Attach a condenser, having lightly greased the joint. Stir and heat the mixture at 70ºC until the solids dissolve. Then raise the temperature to 80ºC with continued stirring. Using a 9" Pasteur pipette, add dropwise 2.25 mL of ethanolic potassium hydroxide solution through the condenser into the flask; make an effort to prevent any drops from contacting the condenser walls . The mixture will immediately turn a dark purple. Once you have added the potassium hydroxide, raise the temperature to about 85ºC. Stir the mixture at this temperature for 15 minutes.

At the end of the heating period, remove the flask from the heat and allow it to cool to room temperature. Then place the flask in an ice-water bath for 5 minutes to complete the crystallization of the product. Collect the deep purple crystals on a Büchner funnel by vacuum filtration. Wash the crystals with 3 4-mL portions of ice-cold 95% ethanol; this wash solvent should be used to transfer crystals from the round-bottom flask to the Büchner funnel if they do not all come out when the mixture is initially poured into the funnel. After air-drying the crystals for a few minutes, complete the drying in a 100ºC-oven for a few minutes.

Weigh the dried product and calculate the percent yield. Also calculate the overall percent yield from benzaldehyde. Determine the melting point. If the melting point is not within 2ºC of the literature value, you should recrystallize your product

Recrystallize your tetraphenylcyclopentadienone from a 1:1 mixture of 95% ethanol and toluene; approximately 24 mL of this solvent mixture will be required per gram of tetraphenylcyclopentadienone, but remember to only add the minimum boiling solvent necessary to dissolve the solute. Recover the crystals by vacuum filtration and redetermine the melting point.

Answer 1