Synthesis of aspirin from methyl salicylate. Exp. 4 - synthesis of salicylic acid from wintergreen oil flashcards.
Clamps and Ring Stand 7. Ten milliliters of 6M Sodium Hydroxide was added to Affair dating unsubscribe milliliters of methyl salicylate in a test tube.
How do we know it is done after 30 minutes? Uses[ edit ] Chick embryo that was treated with methylene blue to stain the skeleton, then cleansed with 2 or 3 ethanol washes, and treated with methyl salicylate to make the surrounding tissues transparent It is used in high concentrations as a rubefacient and analgesic in deep heating liniments such as Bengay to treat joint and muscular pain.
Salicylic acid was combined with acetic anhydride in four test Because the heat generated from adding an acid can possibly super heat the liquid and then the solution may boiling out of the container After HUR, letting the product cool, and adding H2SO4, what should form?
The positively charged sodium disassociates leaving the hydroxide ion with a negative Scheme 1 shows the mechanisms that were demonstrated during the synthesis of Aspirin.
The synthesis of the salicylic acid is done by creating the anion of the acid which is soluble in the aqueous solution. To help push the reaction toward the products, one could distill off the acetic acid. These mechanisms for this experiment can be seen in Scheme 1.
Both the melting points of salicylic acid and aspirin were consistent with the literature values which are degrees Celsius and degrees Celsius respectively.
Another source of product loss was during the filtration of the product. Melting Point Analysis Samples 2.
The structure of aspirin also indicates that there should be a peak for a carbonyl ester, and a carbonyl acid. The purpose of this lab was to demonstrate the ability to easily alter the molecular structure of a compound to greatly increase its utility.
This shows that both the products were relatively pure. Without the addition of the acetyl group, salicylic acid is an irritant to the gastro-intestinal GI tract. The lab demonstrated both the simplicity of the overall reaction, but also a number of considerations regarding the final come which will be discussed in great detail below.
Show where electrons are moving What is the primary solvent in this experiment?
There is probably little to no difference between the Wintergreen Oil synthesis and the Benzene synthesis. Decreased purity - melting point decreased and melting point range broadened because Aspirin would be an impurity in the 1: If not enough acid was added to protonate all the product, some will stay in the aqueous solution and will be lost.
To remove any left over H2SO4 or other left over starting materials from the Salicylic Acid solvent Prevents loss of product yield What can you conclude if the Melting Point of the Salicylic Acid you just synthesized with Wintergreen Oil is and the 1: This was a white powder and had a melting point range of degrees Celsius.
However, these lie in the finger print region of the spectrum and are therefore too hard to differentiate.
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One possibility for loss of product could be during the acidification step. Precipitate Salicylic Acid Why do we acidify to pH 2 or below? The test tube was removed after 20 minutes.