Explain step-by-step procedures for conducting this experiment using organic che

Question

Explain step-by-step procedures for conducting this experiment using organic chemistry lab techniques.

Please help me find out how I should conduct this experiment if I got such scenario in the lab. I need a step by step procudere and also need clarification on the extraction part where which layer would be what (bottom layer vs top layer). I have issues with understanding the layers and finding out which one is which.

Scenario: A student wanted to purify one of the active components in an analgesic drug containing a mixture of components. The active compound of interest to the student is acetanilide. Purify the active compound from the other component, aspirin. Provide data to show that your compound is pure.

Materials Available in the Lab:

Solvents: acetone, ethanol, methanol, ethyl acetate, hexanes, dichloromethane.

Aqueous Solutions: 1 M NaOH, 1 M HCl, 3 M NaOH, 3 M HCl, 1 M NaHCO3, saturated NaCl.

Drying Agent: sodium sulfate

Special Glassware: TLC chambers and plates, separatory funnels

Explanation / Answer

Aspirin is an carboxylic acid (acidic) compound and acetnilide is an amide (neutral).

Separation procedure for acetanilide from aspirin

1) Dissolve both in dichlormethane.

2) Add 1M NaHCO3 to this solution. Bubbles will be seen of CO2(g) comming off. Aspirin reacts with the added NaHCO3 (base) and forms a sodium salt of aspirin which is water soluble. Aqueous layer will be the top layer [density of dichloromethane is greater than H2O].

3) Separate the aqueous layer to another Erlenmeyer flask. Add 3M HCl to it. The aspirin will get protonated and reprecipitation of it occurs. the solid is filtereted and collected as pure aspirin.

4) The organic layer is then dried over sodium sulfate and filtered. The dired organic layer is then evaporate to remove dichloromethane and isolate the acetanilide product.

5) melting point analysis of acetanilide should confirm the purity of the acetanilide.

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