Olivia Isaacs
C127
11 November 2014
The Synthesis and Characterization of Aspirin
Objective:
In this experiment, aspirin was synthesized from acetic anhydride and salicylic acid made in order to characterize its properties and determine its purity. The purity of the aspirin was examined by its melting point, thin layer chromatography, and UV spectroscopy.
Introduction:
Aspirin is synthesized by the formation of acetic anhydride and salicylic acid with the presence of a catalyst (Salicylic Acid + Acetic Anhydride → Acetyl Salicylic Acid + Acetic Acid1). During the synthesis, the catalyst donates an H+ that attaches on to the reaction, but is not consumed.2 Once the salicylic acid has completely dissolved the reaction is complete. Salicylic
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The purity of the aspirin is analyzed by its melting point, thin layer chromatography, and UV spectroscopy. The melting point of a solid is when the molecules have enough thermal energy to overpower their intermolecular forces, breaking the bonds apart.5 This results in the solid turning into a liquid. When observing the melting point, a low melting point indicates more impurities, whereas a high melting point indicates very few impurities in the substance.2 If the substances being tested consist of impurities, the intermolecular forces are weakened causing a lower melting point to be reached. When experimenting …show more content…
The temperature was recorded when melting started and when it finished. When finished, the capillary tubes were removed and the apparatus was shut off.
Thin Layer Chromatography:
A glass jar was obtained and filled with 0.5 cm of the solvent consisting of hexane, ethanol, and ethylacetate. The lid was put on so it could become saturated with vapor.
A TLC plate was obtained and a line was drawn in pencil 1 cm from the bottom. The line was divided into four hash marks (A, SA, P, C).
Add 0.2 g of the aspirin, salicylic acid, pure salicylic acid, and crude were put into labeled test tubes. 1 mL of methanol was added to the test tubes and was then stirred until the crystals dissolved.
The solutions were drawn up using capillary tubes and dotted on the four hash marks on the TLC paper. Each of the dots were spotted twice rather small.
The TLC paper was then put into the glass jar containing the solvent. The lid was put on until the solvent traveled within 2 cm of the top of the plate. It was then removed and the solvent was immediately marked before it dried.
Once the plate dried, it was put under a UV lamp. The spots were marked with a pencil.
UV Spectroscopy:
5 mL of salicylic acid and 8 mL of the iron solution was obtained in a test
From the vial labeled “AE,” aspirin (0.533 g) was placed into a 50 mL Erlenmeyer flask with a boiling stick. Toluene (20 mL) was brought to a boil on a hot plate. The boiling toluene (10 mL) was then added to the aspirin until the solid dissolved completely. After allowing the solution to reach room temperature, the solution was placed in an ice bath for 16 minutes. After the crystals
Separation and Purification of the Components of an Analgesic Tablet. Cora Bruno, Lab Section E. Aspirin, Caffeine and Acetaminophen were separated from four analgesic tablets of Excedrin using extraction techniques. 5% wt/vol NaHCO3, 4M HCL, ethyl acetate and deionized water were used to separate the three active components. MgSO4 was used to dry each extraction. Aspirin was isolated using a hot water bath and weighed to determine the percent theoretical recovery and the actual percent recovery of aspirin. After separation, Aspirin (ASA), Caffeine (CAF), and Acetaminophen (ACE) were purified and identified using Thin Layer Chromatography (TLC). Standards and purified ASA, CAF, and ACE were spotted on the silica gel (stationary phase) of the
The goal of the experiment was to securely isolate pure acetaminophen from p-aminophenol using a synthesis reaction. Synthesis still remains an important tool for scientists conducting chemical reactions. Most synthesis relies on a long process that involves multiple chemicals reactions. In the synthesis of Acetaminophen, one reaction is performed and a four step process is used, Scheme 1. Multiple techniques was used to achieve this goal.
In experiment two, the drug Panacetin was separated by a series of chemical reactions into its three components: sucrose, aspirin, and an unknown active ingredient, either acetanilide or phenacetin. The purpose of this lab was to determine what percentages of each component is present in the pain-killer. The initial step was to dissolve Panacetin in dichloromethane. However, sucrose is insoluble in dichloromethane because organic molecules are soluble in organic solvents, and dichloromethane is an inorganic solvent, so only aspirin and the unknown dissolved. By using gravity filtration, sucrose was filtered from the solution and 0.30g of solid was collected.
If the temperature in the apparatus increases too quickly, it’s difficult to record to exact temperature at which the first drop of liquid falls and then again when the mixture is completely liquid. This would result in the wrong melting point range being recorded. Additionally, experiment three heavily relied on the results from experiment two. Failing to extract all the aspirin from the organic solution in experiment two would result in more impurities in the unknown component. Thus, lowering and broadening the melting point
The first step that needed to be done in this experiment was adding hydrochloric acid (HCl)
The synthesis of acetaminophen involves the attraction of the electrophilic carbonyl group of acetic anhydride to the nucleophilic NH2
3.0g of salicylic acid was weighed then 3.0mL of acetic anhydride and 6 drops of 85% H3PO4 were added to it. The mixture was warmed over a water bath for 5 minutes while stirring. After warming, 20 drops of distilled water was slowly added. 15mL of water was added then the solution was heated until it became clear. It was allowed to cool and was placed in an ice bath until the solution becomes cloudy. Using pre-weighed filter paper, the mixture was filtered and was allowed to dry in the filter paper.
The goal of this experiment was to synthesize aspirin. In this experiment aspirin, also known as acetylsalicylic acid, was synthesized from salicylic acid and acetic anhydride. In the reaction the hydroxyl group on the benzene ring in salicylic acid reacted with acetic anhydride to form an ester functional group. This method of forming acetylsalicylic acid is an esterification reaction. Since this esterification reaction is not spontaneous, sulfuric acid was used as a catalyst to initiate the reaction. After the reaction was complete some unreacted acetic anhydride and salicylic acid was still be present in the solution as well as some sulfuric acid, aspirin, and acetic acid. Crystallization, which uses the principle of
16) Heat some of the hexane to boiling and place the solid to be crystallized into an Erlenmeyer flask.
Both Aspirin and the Unknown are soluble in dichloromethane, due to their non-polar characteristics. To separate the two components, sodium bicarbonate was added (see figure 3). Sodium bicarbonate reacted with aspirin and converted it to a salt, also forming water and carbon dioxide. It was observed that the solution "fizzed" when this reaction took place, showing the release of carbon dioxide. The newly formed salt then traveled to an aqueous layer where it was soluble, while the unknown remained in the dichloromethane layer. The two layers were then separated. To collect an aspirin solid, the combination of the addition of HCl and the process of vacuum filtration helped to break down the salt and form a solid. Then the solid was placed in the Fisher Scientific Biotemp Oven to dry it to a constant mass of 0.091 g, 32.97% of the total composition. The
Of the three components likely to be present in your sample of Panacetin (aspirin, acetanilide, and starch), only starch is insoluble in the organic solvent dichloromethane (or methylene chloride), CH2 Cl2. If a sample of Panacetin is dissolved as completely as possible in dichloromethane, the insoluble starch can be filtered out, leaving acetanilide and aspirin in solution. The purpose of this experiment is to extract the components of Panacetin.
Industrial production of Aspirin is dependent on the company producing the drug; however the general method of production is known as slugging or dry-granulation. In this method, corn starch is mixed with pure water and is then heated and
0.1 gram of salicylic acid was weighed in a tray and was then added to a test tube containing 2.0 mL of Iron (III) chloride, which was measured using a 10 mL graduated cylinder, to test for phenols.
4. Spot the solution on a TLC plate and check with UV light to see