Procedure for Lab 16
Essay by Woxman • November 14, 2011 • Lab Report • 349 Words (2 Pages) • 1,656 Views
1. Place magnetic stir bar and 200mg (.2g) of diphenylmethanol (benzydrol) in a 50mL round bottom flask.
2. Add 10 mL acetone and 0.48mL acetic acid.
3. Remove a couple drops of solution and place in shell vial to use later for TLC
4. Add 15mL bleach and fit condenser to the flask (not nessessary to connect condenser to cooling water)
5. Stir mixture for 5 minutes
6. Remove condenser and use capillary spotter to sample the rxn mixture
7. Spot TLC plate with reaction sample and reference sample
8. Develop the TLC plate using a 30% acetone/70% hexanes solution
9. View under UV light
10. The reaction is complete if you observe no starting material in the reaction sample line If the reaction is incomplete add another 2 mL of bleach and stir for another 5 minutes
11. Anaylze the reaction mixture again by TLC. Repeat this process until the reaction is complete
12. When the reaction is complete, pour the reaction mixture into a 125 mL separatory funnel
13. Add 5 mL of hexanes to the reaction round bottom flask and swirl to extract any product in the flask.
14. Add the hexanes solution to the 125 mL separatory funnel.
15. Extract the reaction mixture with the hexanes and separate the layers.
16. Collect the organic layer and return the aqueous layer to the separatory funnel.
17. Repeat the extraction with a second 5 mL portion of hexanes.
18. Combine the hexanes layers.
19. Remove the aqueous layer from the separatory funnel and set it aside.
20. Add the hexanes layer to the separatory funnel and extract with 2 mL of 5% sodium bicarbonate solution.
21. Extract with 3 mL of water.
22. Remove the hexanes layer from the separatory funnel and dry over drying agent (magnesium sulfate or sodium sulfate).
23. Vacuum filter the dry hexanes solution using a Hirsch funnel.
24. Transfer the dry hexanes solution to a pre-weight 50 mL beaker.
25. Evaporate the hexanes on the steam bath.
26. Use a stream of air (very low flow rate) to complete the evaporation. If get an oil ask for help with the final crystallization.
27. Weigh
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