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This is the text of Purity's computer file document, lab2.txt, the last chemistry lab write up she completed with lab partner Kevin Stark.
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Fundamentals of Organic Chemistry
Chemistry 223 - Section 4: Coulter Hall Lab
Unit: Aldehydes and Ketones
Ariadne P. Knight & Kevin T. Stark
February 14, 1997
 
Aldol Condensations on Supported Reagents
 
Equipment:
 
8 mL SPE reservoir with frit
stopcock
reservoir support and bracket
beaker
cut tip transfer pipet
1 mL calibrated transfer pipet
test tube
microliter syringe
safety equipment, goggles, gloves
MSDS sheets
 
Purpose:
 
Analyze the solution to determine the percent conversion of reactant to product, and isolate and purify product. Accomplish condensations using SPE tubes and ion-exchange resins for Chalcone, Dibenzalaceton, Monobenzalacetone.
 
Procedures:
 
Step 1. Fit 8 mL SPE reservoir with closed stopcock and support. Ensure frit pressed evenly in bottom.
Step 2. Wash basic anion exchange resin, Amberlite IRA-400 (OH) in 0.5 mmol each of benzaldehyde and acetophenone by creating a slurry of resin in the solvent.
Step 3. Add 2 mL of resin to resevoir using cut tip transfer pipet.
Step 4. Allow resin to settle.
Step 5. Once resin has settled, the stopcock is opened and solvent allowed to drain from the reservoir.
Step 6. Mix reagents to be used in a test tube with 0.5 mL solvent to solution and transfer to top of resin bed in reservoir with poly transfer pipet. Wash test tube with another 0.5mL solvent and add to reservoir.
Step 7. As necessary, add solvent until 1 to 2 mm above the top of the resin bed ensuring that the reaction solution is in contact with the entire resin bed.
Step 8. Agitate gently to to mix reagent solution. Using a 1 mL calibrated poly transfer pipet, insert to bottom of resin bed and squeeze bulb slowly.
Step 9. Allow solution to stand for 30 minutes. As necessary for crystallization, add enough solvent to dissolve product.
Step 10. Open stopcock and allow the contents to drain into flask. Wash resin with one bed-volume of solvent.
Step 11. Analyze the solution to detemine the percent conversion of reactant to product, and isolate and purify the product.
 
Specific Procedures:
 
1. For Chalcone, use 0.5 mmol each of benzaldehyde and acetophenone
2. For Dibenzalacetone, use 0.25 mmol of acetone and 0.50 mmol of benzaldehyde
3. For Monobenzalacetone, use 0.25 mmol of benzaldehyde and 2.0 mmole of acetone
 
(Kevin's observations and our conclusions here, Kevin thinks we should print out separately and just copy)
 

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