Isolation of Components of Bc Powder

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Isolation of the Components of BC Powder

Introduction

Aspirin, Caffeine and Salicylamide were extracted from an over-the-counter pain reliever (BC Powder). These components were separated by manipulating their solubilities by adjusting the acidity and basicity of the solution. By doing this, the three components were forced into conjugate acid (or base) forms, causing selective solubility in either an aqueous or organic solvent. These layers were then separated by use of a separation funnel. Once separated, the components extracted were characterized by measuring the melting point and performing a TLC analysis. Also, the recovered aspirin from the first part of the experiment was recrystallized and compared to that of the isolated aspirin.

Reactions

Formula MW equivalence MP (ºC) Density (g/mL)

C9H8O4 180.16 1 135 --

NaHCO3 84.01 1 50 2.20

C9H7NaO4 202.14 1 ---

H2O 18.02 1 0 1.00

CO2 44.01 1 -56.56 0.720

Formula MW equivalence MP (ºC) Density (g/mL)

C9H7NaO4 202.14 1 ---

HCl 36.46 1 114.17 0.00149

C9H8O4 180.16 1 135 --

Formula MW equivalence MP (ºC) Density (g/mL)

C10H14N4 190.24 1 236.3 1.23

HCl 36.46 1 159 0.00149

C10H15ClN4 226.71 1 ---

Formula MW equivalence MP (ºC) Density (g/mL)

C10H15ClN4 226.71 1 ---

NaOH 40.00 1 323 2.13

C10H14N4 190.24 1 236.3 1.23

NaCl 58.44 1 800.7 36

H2O 18.02 1 0.0 1.00

Experimental procedure:

Aspirin (1.30 g , 0.00722 mol), Caffeine (0.00666 g, 0.000350 mol) and Salicylamide (0.390 g, 0.00284 mol) were combined in a 100 mL beaker. To this beaker, ethyl acetate (20 mL) and saturated NaHCO3 (10 mL) were added. The organic and aqueous layers were allowed time to separate before the organic layer was removed and put aside. An additional portion of NaHCO3 solution (10 mL) was added and the separation was repeated. The aqueous layer was put aside in a beaker labeled “NaHCO3 Extract.” To the organic layer still in the separatory funnel, 3M HCl (10 mL) was added. The resultant aqueous layer was drained and additional 3M HCl (10 mL) was added. This second aqueous layer was then drained into a beaker labeled “HCl Extract.” The remaining organic layer was drained into a beaker labeled “Organic Layer.”

To the beaker labeled “Organic Layer”, 2 scoops of magnesium sulfate were added. The contents of the beaker were then gravity filtered into a round bottom flask. This flask was then attached to a rotary evaporator and the solid was removed and placed in a vial labeled “OE” (Organic Extract).

To the beaker labeled “NaHCO3 Extract”, 6M HCl (2 mL) was added to bring the pH to 6. After this, additional 6M HCl (10mL) was added. The solution was then vacuum filtered and washed with cold water. The solid was transferred to a vial labeled “BE” (Basic Extract).

To the beaker labeled “HCl Extract”, 6M NaOH (2 mL) was added to bring the pH to 8. After this, additional 6M NaOH (10mL) was added. To the beaker, ethyl acetate (10 mL) was added. The aqueous and organic layers were separated. The organic layer was drained into an Erlenmeyer flask. This solution was then treated with 3 scoops of magnesium sulfate. The solution was then gravity filtered into a round bottom flask. This flask was then attached to a rotary evaporator. After evaporation, the solid was transferred to a vial labelled “AE” (Acidic Extract).

Three test tubes were then set up with small amounts of standard compounds of acetylsalicyclic acid (labelled “A”), caffeine (labeled “C”) and salicylamide (labeled “S”) dissolved in 5 drops of acetone. Three more tubes were set up with small amounts of the solids from the vials labeled “OL”, “AE” and “BE.” Acetone (5 mL) and hexane (5 mL) were then combined to make the developing solvent. A half-circle of filter paper was set into a 100 mL beaker and the bottom was covered with the developing solvent. A TLC plate was then prepared with a spot for each of the six test tubes. The TLC plate was then placed in the beaker...
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