BACKGROUND: Add 10 packets of artificial sweetener to a tared beaker & record the weight

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BACKGROUND:

1. Add 10 packets of artificial sweetener to a tared beaker & record the weight.
2. Mass of sweetener= 9.78 g
3. Add 25 mL of acetone/ethyl acetate (98: solution to the beaker with the sweetener and stir for 5 minutes.
4. Allow undissolved solid to settle and filter the liquid into a 250 mL round bottom flask.
5. Repeat steps 2 & 3 twice more with the solid remaining in the beaker, filtering the liquid into the same 250 mL round bottom flask each time, then proceed to step 5.
6. Remove the solvent using a rotary evaporator (rotovap).
7. Once the solvent is removed, add 20 mL of acetone/ethyl acetate solution and swirl. Once again, not all the solid in the flask will dissolve.
8. Filter the liquid into a tared 50 mL round bottom flask and concentrate the extract using the rotary evaporator.
9. Removal of solvent should yield 100-200 mg of clear syrup-like product. Record mass and yield.
10. Mass of extract= 188 mg
11. To the flask containing the sucralose extract, and 0.5 mL of pyridine and 300 μL of acetic anhydride, along with a magnetic stir bar. The acetic anhydride is in excess of what is needed for the reaction to run to completion
12. stir the reaction at room temperature for 75 minutes.
13. Add 10 mL of ethyl acetate to the flask and transfer to a separatory funnel. Rinse the round bottom flask with another 10 mL of ethyl acetate and combine with the first portion in the separatory funnel.
14. Wash the organic layer with 50 mL of 10% HCl, then 40 mL of DI water, then with 25 mL of brine.
15. Isolate the organic layer and dry with anhydrous sodium sulfate.
16. Filter the dry organic layer and rinse the sodium sulfate with additional ethyl acetate.
17. prepare the TLC plate by spotting the organic layer and a standard solution of artificial sweetener dissolved in MeOH.
18. Develop the TLC plate in 1:1 hexane/ethyl acetate.
19. Concentrate the product solution using a rotovap. Weigh the flask, calculate yield of your crude acetylated product, and obtain the melting point of your crude product.
20. Mass of crude product= 167 mg
21. MP= 92-95 ?C

QUESTION 8: What is the percent yield of your crude acetylated product? Use the mass of your extracted sucrose to calculate theoretical yield.

1. Purify the product using a silica column using 2:1 hexane/ethyl acetate as the eluent.
2. Dissolve your crude sample in 0.5 mL of hexane/ethyl acetate and load the dissolved sample onto the column.
3. Run 20 mL of eluent through the column, then collect 10 fractions of ~2 mL each. After your 10^th fraction, run another 20 mL of eluent through the column
4. Use TLC to determine which fractions contain pure product. Combine these fractions and concentrate by rotovap
5. Once sample volume is 1-2 mL, add 3 mL cold hexane to the solution and submerge the flask in an ice bath
6. Once crystals have formed, isolate your product by vacuum filtration and dry the crystals over vacuum.
7. Record the mass of your crystals and obtain the melting point, IR, ¹H NMR, and ¹³C NMR.
8. Mass of purified product= 113 mg
9. MP= 98-100 ?C  

QUESTION 12: What is the percent yield of the purified acetylation product? Use the mass of your extracted sucralose to calculate theoretical yield.

 

These are the two questions again.

QUESTION 8: What is the percent yield of your crude acetylated product? Use the mass of your extracted sucrose to calculate theoretical yield.

QUESTION 12: What is the percent yield of the purified acetylation product? Use the mass of your extracted sucralose to calculate theoretical yield.