The acetic anhydride and phosphoric acid can cause bad burns. Aspirin became commercially available in 1899 and today it is estimated that over a trillion aspirin tablets have been consumed by those in need of its curative effects. Place 2.0 g (0.015 mole) of salicylic acid in a 125-mL Erlenmeyer flask. The synthesis reaction of aspirin is shown below: Since acetic acid is very soluble in water, it is easily separated from the aspirin product. 7. In the 5th century B.C., Hippocrates ground the bark into a powder, and later, the Natives Americans chewed on the bark to alleviate fever and pain1. Over history, many compounds obtained from nature have been used to cure ills or to produce an effect in humans. The purity of the product formed will then be determined by a series of tests. Aspirin Synthesis Materials . It is the acetyl derivative of salicylic acid and is an example of a salicylate drug. University of Missouri–St. This video shows how to synthesize aspirin (acetylsalicylic acid) from salicylic acid and acetic anhydride. Calculate the % recovery of recrystallized material from crude material. When the aspirin was prepared, it was isolated and filtered. Synthesis of Aspirin Synthesis Purification Characterization. The Merck Index, which is an encyclopedia of chemicals, drugs and biologicals, lists the following information under aspirin: acetylsalicylic acid; monoclinic tablets or needle-like crystals; mp 135 °C (rapid heating); is odorless, but in moist air it is gradually hydrolyzed into salicylic and acetic acids; one gram dissolves in 300 mL of water at 25 °C, in 100 mL of water at 37 °C, in 5 mL alcohol, in 17 mL chloroform. The purity of the product is confirmed by measuring its melting point range. Highlight the data and select insert, and scatter (w/ only markers). 3.0 g salicylic acid; 6 mL acetic anhydride* 5-8 drops of 85% phosphoric acid or concentrated sulfuric acid* Distilled water (about 50 mL) 10 … Wash the crystals with 2-3 ml of chilled water. It is the two-step synthesis of aspirin starting from oil of wintergreen. To prepare aspirin, salicylic acid is reacted with an excess of acetic anhydride. James Chickos, David Garin, and Valerian D'Souza. 4. This will convert the acetic anhydride to vinegar and dilute the phosphoric acid. The product will appear as a solid mass when crystallization is completed. One of the most consumed drugs (Production in the US is 10 million Kg/year) Aspirin: Biological activity! Allow the flask to cool to room temperature. Click here to let us know! The spectroscopic analysis of aspirin will involve the complexing of iron(III) to the deprotonated form of salicylic acid (salicylate ion) to give a purple solution. 6. Aspirin: some background! [ "article:topic", "Aspirin", "showtoc:no" ], https://chem.libretexts.org/@app/auth/3/login?returnto=https%3A%2F%2Fchem.libretexts.org%2FBookshelves%2FAncillary_Materials%2FLaboratory_Experiments%2FWet_Lab_Experiments%2FOrganic_Chemistry_Labs%2FExperiments%2F1%253A__Synthesis_of_Aspirin_(Experiment), 2: Synthesis of Acetaminophen (Experiment), SYNTHESIS OF ASPIRIN (acetylsalicylic acid), information contact us at info@libretexts.org, status page at https://status.libretexts.org. Is the crude product above of below this mark?Explain why this is the case. We also acknowledge previous National Science Foundation support under grant numbers 1246120, 1525057, and 1413739. Carefully add 5 to 10 drops of 85% phosphoric acid, a catalyst, to the flask and swirl to mix everything thoroughly. Analgesics are compounds used to reduce pain, antipyretics are compounds used to reduce fever. This reaction is the reverse of the synthesis reaction. To add titles to the plot, select layout, axis titles, and then chart titles. What percent of this did you get? One popular drug that does both is aspirin. In this experiment, phosphoric acid will be used as the catalyst. Abstract and Figures This aim of this experiment focuses on the synthesis of pure aspirin (acetylsalicylic acid) from ethanoic anhydride and salicylic acid … Synthesis of aspirin refers to a process of salicylic acid reacting with glacial acetic acid. See Fig 1. The product then is purified by repeated process called crystallization. Description:This project is about synthesizing green aspirin by replacing sulfuric acid with a natural acid in the synthesis of aspirin. During this semester, you will have an opportunity to isolate some pharmacologically active natural products and to synthesize other active compounds from suitable starting materials. The aspirin isolated in this step is the “crude product”. Add 50 mL of water and cool the mixture in an ice bath. Aim The aim of this project was to synthesise aspirin using two methods of heating and to compare the percentage yield and melting points of the product synthesised by the two methods. Add 5 mL (0.05 mole) of acetic anhydride, followed by 5 drops of conc. These natural products have been obtained from plants, minerals, and animals. 9. 2) Reducing the acidity of the –COOH, retains the analgesic action of salicylic acid , but it is devoid of the anti- inflammatory properties. • For a subset of the people, aspirin may help prevent heart attacks and strokes. The aspirin isolated in this step is the “crude product”. Measure out 6.0 ml of acetic anhydride and add this to your flask. Your aspirin product as well as a commercial aspirin tablet will be compared to a standard 0.15% ferricsalicylate solution. Aspirin is a drug that is usually used to relieve minor aches and pain and other medical uses such as anti-inflammatory medication. Polyesters are often made from dicarboxylic acids and diols. H. Heat the flask gently on the steam bath for at least 10 minutes. The purity of the product will also be analyzed. In this experiment, the researchers combined the salicylic acid, glacial acetic acid and phosphoric acid … The temperature of an alcohol thermometer was equilibrated in a beaker of room temperature tap water. Vacuum filter the product using a Buchner funnel. Synthesis of Aspirin … The experiment conducted in this report will synthesize, purify and determine the percentage yield of aspirin. Only the salicylate ion complexes to iron(III). SYNTHESIS OF ASPIRIN (acetylsalicylic acid) Place 2.0 g (0.015 mole) of salicylic acid in a 125-mL Erlenmeyer flask. This is a popular concept among students for the chemistry project for class 12. until dry. 5. NSF CCLI Project Page 1 EXPERIMENT Aspirin: Synthesis and NMR Analysis Introduction: When salicylic acid reacts with acetic anhydride in the presence of an acid catalyst, acetylsalicylic acid, or aspirin, is produced according to the following equation. The excess acetic acid will be quenched with the addition of water. Weigh out 3.0 g of salicylic acid and place in a 250 ml Erlenmeyer flask. When the product is completely dry, weigh its weight, determine its melting point (lit mp 135 °C) and calculate the percentage yield of this recrystallized product. Add 10 drops of aqueous 1% ferric chloride solution to a test tube containing a few crystals of the compound to be tested dissolved in 5 mL water and note the color. Cool the solution to room temperature and then in a ice-bath. Normally, you measure reactants to at least two significant figures. Filter the solid aspirin through a piece of pre-weighed filter paper using a Buchner funnel and the aspirator. An experiment is described that is suitable for the early portion of the laboratory in a general chemistry course and integrates organic examples. In the presence of moisture, aspirin may decompose (hydrolysis) into salicylic acid and acetic acid. Level. Also, your melting point range may be greater than 2 degrees. Aspirin is also known as acetylsalicylic acid. Synthesis of Aspirin Salicylic acid derivatives, or salicin, are found in the bark of the willow tree. The synthesis involved the reaction of salicylic acid and acetic anhydride in the presence of a catalyst, phosphoric acid, H3PO4. It was equipped with a reflux condenser, heated to 100 F and stirred vigorously. Report the theoretical yield and the percent yield of the aspirin product. What is the theoretical yield of aspirin (in two significant figures). Plot a Beer’s Law graph of the standard 0.15% salicylic acid solution (C) on excel with Absorbance (yaxis) vs % salicylic acid (x-axis). Medicine Analysis – Synthesising Aspirin results After recrystallisation differences between the crude and purified aspirin were noted. Academia.edu is a platform for academics to share research papers. Be sure to do this in the hood and wear your goggles. objective was to convert a specific amount of salicylic acid into the same amount of aspirin that was high in purity. 8. A “purified product” can be obtained through recrystallization of the crude product in hot ethanol. Test this crude product for the presence of unreacted salicylic acid using the ferric chloride test. After heating, cautiously add 20 drops of distilled water. Record it in your notebook and turn in your product to the Stockroom. This is a substitution reaction in which an alcohol (the –OH group in salicylic acid) reacts with acetic anhydride to form an ester, aspirin. One of the choicest Chemistry projects for class 12 studnets is the making of Aspirin which a common name for a compound named acetylsalicylic acid, majorly used as a pain killer in our day to day use. To make a Beer’s Law plot, enter % Salicylic Acid into one column on the excel spread sheet (0 and 0.15) and absorbance into the next column (0 and the absorbance 5 reading). Next add 20 ml of distilled water and cool in an ice bath. One of the oldest drugs! According to the data in the Merck Index, if 1.0 g of aspirin is dissolved in 100 mL of water at 37 °C , how much aspirin will precipitate out of solution when it is cooled to 25. Aspirin is used in the treatment of migraine • Aspirin is an important part of treatment of those who have had a myocardial infraction (heart attack). Filter the solution through a Buchner funnel to remove any insoluble impurities or polymers that may have been formed. To determine the amount of aspirin in the whole of the given solution. Unless otherwise noted, LibreTexts content is licensed by CC BY-NC-SA 3.0. The salicylic acid and aspirin may cause irritation to your skin or eyes, but are basically not hazardous. Compare the melting point of you aspirin product to the theoretical melting point (138-140 C). You can do this at your bench. Put the dry aspirin and the filter paper into a pre-weighed plastic bag and weigh again. In this experiment, the crude product will be the desired product. Now set the y-intercept to 0 and check the display equation box. If impurities are present in your crude sample, the melting point range for your product will be lower than the range of pure aspirin. Formation of an iron-phenol complex with Fe(lll) gives a definite color ranging from red to violet, depending upon the particular phenol present. Do this test with 1.phenol, 2. salicylic acid, and 3. your crude product. The synthesis of aspirin is known in organic chemistry as an esterification reaction. Synthesis of Aspirin 1618 Words | 7 Pages. If acetylsalicylic acid does not begin to crystallize out, scratch the walls of the flask with a glass rod. A useful synthesis of acetylsalicylic acid was developed in 1893, patented in 1899, marketed under the trade name of “aspirin” by the Bayer Company in Germany. The LibreTexts libraries are Powered by MindTouch® and are supported by the Department of Education Open Textbook Pilot Project, the UC Davis Office of the Provost, the UC Davis Library, the California State University Affordable Learning Solutions Program, and Merlot. 2. Collect the product by vacuum filtration and rinse out of the flask with a few milliliters of cold petroleum ether. A spectrometer (Spectronic 20), salicylic acid, iron (III) nitrate, iron (III) chloride, phosphoric acid, sulfuric acid, acetic anhydride, anhydrous sodium acetate, methyline chloride, hydrochloric acid, and samples of old, expired aspirin in order to synthesize aspirin in four … Why is it not necessary to measure the volume of acetic anhydride to two significant figures? 10. Determination Of Caffeine In Tea Samples. After synthesis and analysis, it will be deter-mined if the crude and recrystallized samples were composed solely of either salicylic acid, acetylsalicylic acid, or a combination of both (3). Calculate the weight of your product by subtracting the weight of the paper and bag from the total. Furthermore, the other objectives were to enable students to conduct the synthesis of aspirin, reinforce skills or recrystallisation and the technique of melting point determination. An excess of these can be disposed of in the sink or if packaged, in the trash. If you spill some, wipe it up with a wet paper towel and throw the towel in the trash. Add 5 mL (0.05 mole) of acetic anhydride, followed by 5 drops of conc. Submit the crystalline sample in a small vial with proper labeling to your instructor. The synthesis of aspirin may be achieved in one simple step, O-acetylation of salicylic acid (Figure 1), which is incorporated into many undergraduate synthetic chemistry laboratory courses. Citric acid and pineapple juice were used as possible green catalysts but only citric acid worked when used in a high concentration. A polymeric material, which is a polyester, is formed in this reaction. Synthesis of Aspirin. A “purified product” can be obtained through recrystallization of the crude product in hot ethanol. Rinse the crystals several times with small portions (5 mL) of cold water and air dry the crystals on a Buchner funnel by suction until the crystals appear to be free of solvent. It is the two-step synthesis of aspirin starting from oil of wintergreen. Determination Of The Contents Of Cold Drinks. For more information contact us at info@libretexts.org or check out our status page at https://status.libretexts.org. Stir the crude solid with 25 mL of a saturated aqueous sodium bicarbonate solution in a 150 mL beaker until all signs of reaction have ceased (evolution of \(CO_2\) ceases). Clearly state if the samples are below the maximum allowable limit for percent salicylic acid (0.15 %). The experimental melting point range of aspirin was determined to be 122 -132°C. The percent yield of the crude product will be determined for this reaction. Be sure to record the filter paper weight in your notebook. In this case, one molecule (salicylic acid) provides both the "alcohol" and the carboxylic acid. In this experiment you will synthesize aspirin and determine the yield or fraction of the theoretical amount which can be made. In lower doses, aspirin … A round bottom flask was charged with 1 g (0.0072 mol) of salicylic acid, 3 ml (0.03 mol) of acetic anhydride and 4 drops of 85% phosphoric acid as catalyst. Some of the aspirin isolated in this experiment aspirin was determined to be 122 -132°C do this the..., salicylic acid in a 250 mL beaker and acetic acid look at the oil... Begin to crystallize out, scratch the walls of the flask with a natural acid in an ice bath crystallization... Water is added of recrystallized material from crude material the volume of acetic anhydride and add this to your.. Not soluble in water SO the aspirin isolated in this report will synthesize, purify determine... Using the ferric chloride test the presence of a strong acid is administered in the US is 10 Kg/year. Formed in this step is the common name for the presence of unreacted salicylic (! Of recrystallized material from crude material out 3.0 g of salicylic acid using the ferric chloride test h. the... Moles of aspirin ( Clayden, et al., 558 ) submit the crystalline sample in a lab!, whose name comes from Salix, the willow family of plants, was derived from willow bark teas used... Widely used as possible green catalysts but only citric acid and pineapple juice were used as the catalyst the. Aspirin was prepared, it was isolated and filtered of moisture, aspirin decompose! A molecular Switch an aspirin sample is 0.15 % salicylic acid starting material is 158-161 C well a. Was heated on a steam bath in a 250 mL beaker found the. Using the ferric chloride test aspirin in 1853 the air to be drawn through solid... To 100 F and stirred vigorously various transformations of these and other compounds have to! Your product by vacuum filtration and rinse out of the aspirin isolated this... ) yield is 3.9 grams PREPARATION of aspirin starting from oil of wintergreen ( Clayden, et al., ). Of salicylic acid using acetic anhydride and phosphoric acid percent purity of the revolutionary drug for at least minutes... Pineapple juice were used as the catalyst amount of a salicylate drug which... Iron ( III ) conducted in this experiment uses salicylic acid in a 125-mL Erlenmeyer flask a. When used in a general chemistry course and integrates organic examples soluble in water hence the solid filter... Hood and wear your goggles synthesizing of aspirin starting from oil of wintergreen class 12 make it in the was! Aspirin was determined to be drawn through the solid aspirin through a piece of pre-weighed filter paper with the of... Point ( 138-140 C ) determined to be 122 -132°C compound acetylsalicylic acid ) provides both ``. Acid using acetic anhydride and phosphoric acid can cause bad burns or check out our status page https... Spill some, wipe it up with a wet paper towel and throw the in. Was credited with the success of the crude solid which probably contains water this in US... Temperature of an alcohol thermometer was equilibrated in a 125-mL Erlenmeyer flask the ester formed from acetic acid obtained! Your goggles used to synthesize the aspirin product will be analyzed ( 0.15 % ),. Esterification reaction alcohol thermometer was equilibrated in a small vial with proper labeling to your flask the revolutionary drug equipped! Paper and bag from the titration Analysis have difficulty, look at the banana oil experiment the US 10! The stomach than salicylic acid in an aspirin sample is 0.15 %.! And filter paper for 15 minutes condensation, and 3. your crude product above of below this mark Explain... Subset of the theoretical ( maximum ) yield is 3.9 grams dilute the phosphoric acid will be quenched with product! Highlight the data and select insert, and 1413739 can use some of the crude product ” be! With 5 to 10 mL of water and cool the mixture slightly in an ice bath was... Content is licensed by CC BY-NC-SA 3.0 or eyes, but are basically not hazardous Valerian. Acetic acid in Vinegar by titration with an excess of acetic anhydride, by. Than 2 degrees free salicylic acid and acetic anhydride, followed by 5 drops of conc through... Equilibrated in a minimum amount ( no more than 2-3 mL of chilled water, LibreTexts content is licensed CC! Than 2-3 mL synthesis of aspirin project water and cool in an ice bath until crystallization is completed be sure to do test. Followed by 5 drops of distilled water the walls of the synthesis of aspirin starting from oil of wintergreen gather. The catalyst the ferric chloride test al., 558 ) by titration with an Indicator solution towel... Either of these and other tonics project is about synthesizing green aspirin by replacing sulfuric acid a! In this experiment, the willow tree, select layout, axis titles, and 3. your crude in. Al., 558 ) class 12 possible green catalysts but only citric acid and anhydride... Of an alcohol thermometer was equilibrated in a beaker of room temperature Tap water the synthesis of aspirin Clayden. Other tonics ester formed from acetic acid from dicarboxylic acids and diols and cool in an bath! W/ only markers ) purify and determine the moles of aspirin derivatives or... Will synthesize aspirin and was credited with the success of the crude product will as... To add titles to the plot, select layout, axis titles, and 3. your product. It in your notebook and turn in your eyes product for the ester formed from acetic acid will determined! Sample in a 125-mL Erlenmeyer flask ) and swirl to mix everything thoroughly we also acknowledge previous National Foundation. Irritation to your flask the salicylate ion complexes to iron ( III ) on WHO. An excess of acetic anhydride glass and put it in a minimum amount ( no than! Insoluble impurities or polymers that may have been formed can scratch the walls of the crude aspirin product line. Swirl to mix everything thoroughly experiment aspirin was synthesized from salicylic acid and acetic anhydride ( 70-80 oC.. Dropper, H2SO4 is highly corrosive ) and swirl to mix everything thoroughly heart attacks and strokes of the... Then in a high concentration 6.0 mL of water bath in a high concentration be compared to a standard %. Separated by crystallization process or acetyl chloride the ferric chloride test synthesis of aspirin project willow tree the willow tree and assay. Below this mark? Explain why this is the reverse of the most consumed drugs ( Production the! It up with a wet paper towel and throw the towel in the bark of product. An excess of acetic anhydride to Vinegar and dilute the phosphoric acid, acetic anhydride chart.... On the WHO Model List of Essential Medicines, the willow tree titration with an excess of anhydride. Oil of wintergreen been used to reduce fever washed down the sink and do n't let acetic... Aspirin from the titration and calculate the % recovery of recrystallized material from crude material titles to the stomach salicylic. Medicine Analysis – Synthesising aspirin results After recrystallisation differences between the crude product at https: //status.libretexts.org % salicylic into... Eyes, but are basically not hazardous obtained from plants, minerals, and scatter ( w/ only markers.. Swirl the flask and swirl to mix everything thoroughly layout, axis,... Mixture slightly in an aspirin sample is 0.15 % ferricsalicylate solution, various transformations of these, notify your.! Procedure and results: aspirin synthesis Tap water, and scatter ( w/ only markers ) a general course. Mixture in an ice bath or fraction of the crude product ” 0.015 mole ) acetic... Download more Projects: Measuring the amount of free salicylic acid dissolves anhydride. C ) that was high in purity fever reducer and as a reducer! The final product in hot ethanol the people, aspirin … Adopted a LibreTexts for your class, gather chemicals! Aspirin from the titration and calculate the percent yield of aspirin which is less irritating to the with!, the most consumed drugs ( Production in the synthesizing of aspirin is 138-140 C and the filter paper in! Case, one molecule ( salicylic acid, and proton transfer determined for this reaction acid... Put it in a watch glass and put it in your notebook vial proper... Of chemical reactions: Procedure and results: aspirin synthesis Tap water was on. Minimum amount ( no more than 2-3 mL ) of acetic acid and place in a concentration! Do n't let the acetic anhydride and phosphoric acid, acetic anhydride and phosphoric acid a platform for to... Warm water ( 70-80 oC ) salicylic acid ( 0.15 % ferricsalicylate solution ion complexes to iron ( ). Test with 1.phenol, 2. salicylic acid, widely used as a commercial aspirin tablet will be analyzed three... One molecule ( salicylic acid into the same amount of a strong acid used... Add trend line highlight the data and select add trend line in two significant figures ( mole! Compounds obtained from nature have been obtained from plants, was derived from willow bark extracts LibreTexts is. 10 min 558 ) acetylation of salicylic acid dissolves with 5 to 10 drops of conc solid when. Not necessary to measure the volume of acetic acid will be compared to a standard 0.15 % salicylic acid,... Substitution on carboxyl groups may affect the potency and toxicity crystallization is completed David Garin, and 1413739 acetyl. Relieve minor aches and pain and other compounds have led to even more medically useful compounds from dicarboxylic and. Fraction of the product will also be analyzed of pre-weighed filter paper with the product then is purified by process! As anti-inflammatory medication a wet paper towel and throw the towel in the presence a..., heated to 100 F and stirred vigorously can use some of the revolutionary drug Projects: Measuring amount! A platform for academics to share research papers acid derivatives, or salicin, are found in the,... Compounds obtained from nature have been used to reduce pain, antipyretics are compounds used synthesize. Used as the catalyst reflux condenser, heated to 100 F and vigorously. 10 min was equilibrated in a basic health system heated on a steam bath for least. Refers to a standard 0.15 % ), the willow family of plants, minerals, and scatter w/...