Preparation of salicylic acid:
Place 2g of salicylic acid into dry conical flask. Add 5 mL acetic anhydride and 5 drops of 85% phosphoric acid. Swirl the mixture and heat on a steam bath for 5 minutes.
Remove flask form the steam bath and whilst still hot add 2 mL of water in one portion to decompose excess acetic anhydride. Why add the reaction mixture while it is still hot?
Preparation of salicylic acid:
Place 2g of salicylic acid into dry conical flask. Add 5 mL acetic anhydride and 5 drops of 85% phosphoric acid. Swirl the mixture and heat on a steam bath for 5 minutes.
Remove flask form the steam bath and whilst still hot add 2 mL of water in one portion to decompose excess acetic anhydride. What is the appropriate equation for this reaction?
Reaction mixture is added while hot because aspirin is very little soluble in water thus in hot water it is more soluble.
Reaction :

Preparation of salicylic acid: Place 2g of salicylic acid into dry conical flask. Add 5 mL...
used. Experimental . Place 2.0 g of salicylic acid in a 125-mL conical flask. 2. Add 4.0 ml (d = 1.08 g/mL; 4.3 g) of acetic anhydride and 6-8 drops of 85% phosphoric acid. 3. Swirl the flask to mix all reagents, and place it in a 70°C water bath. Heat for about 10 minutes. 4. Remove the flask from the water bath and add 2 mL of cold water drop- wise, swirling the flask after each addition, 5. Add...
Place 3.0 g of salicylic acid in a 125-ml Erlenmeyer flask. Carefully add, stirring constantly, 6 mL of acetic anhydride, followed by 10 drops of concentrated sulfuric acid. Swirl the contents of the flask so that the reactants are thoroughly mixed. Stopper the flask with a one- hole cork fitted with an inverted Pasteur pipet to prevent condensation of water in the reaction flask during heating on the steam bath. Heat the flask in a boiling-water or steam bath for...
find the theoretical yield of the acetysalicylic acid .
EXPERIMENT 19 PREPARATION OF ASPIRIN In addition to the Fischer esterification method presented in Experiment 18, a second method for preparation of esters involves the reaction of anhydrides with the hydroxyl This method is ospecialy usoful for tho preparation of acetate esters, since acetic anhydride is an inexpensive and reactive reagent. In this experiment the hydroxyl group of salicylic acid is acetic anhydride to make acetylsalicylic acid, or aspirin. The short...
Pre-lab Questions:
Importance A one-step preparation of aspirin from its precursor, salicylic acid, via an ester formation illustrates one of synthetic organic chemistry's most important uses, making the drugs that treat all types of illnesses. OH HOOH Background Aspirin is a prodrug of salicylic acid, the actual active drug. A compound related to salicylic acid, salicin, was first isolated from willow bark in the mid 1700's, but willow-bark extract was used by the ancient Greeks as a treatment for pain...
PROCEDURE 1. Place a reaction tube into a 5-mL Erienmeyer and tare. Add between 0.275- 0.300g of salicylic acid. Record on the data sheet. 2. Transfer the reaction tube and 5-ml Erienmeyer to the hood. Add a boiling chip, 2 drops of 85% phosphoric acid, and about 0.70 mL of acetic anhydride to the reaction tube. Mix well. 3. Place a 50-ml beaker containing about 20-mls of water on a hot plate or in the sand bath. Allow the water...
2g of salicylic acid, add
5ml of acetic anhy drib, add
5 drops of concentraded sulfric acid. if
2g of salicylic acid used in the experiment,
determine the number of moles of salicylic acid
UML CHEM 1140L 1e) Calculate the molecular mass of acetylsalicylic acid. (show your work) (4 pts) 1f) If 2g of salicylic acid used in the experiment, determine the number of moles of salicylic acid. (show your work) (6 pts) 1g)...
Calculate theoretical and percent yield. In this experiment, salicylic acid and acetic anhydride will be reacted to form acetylsalicylic acid in an acid catalyzed reaction. In a reaction tube, add approx. 140 mg salicylic acid, a boiling chip and a small drop of 85% phosphoric acid. Add 0.3mL acetic anhydride, which should wash the reactants to the bottom of the tube. Mix thoroughly. Heat in a beaker of water at 90oC for 5 min. Cautiously add 0.2 mL water to...
Write out your separation scheme for this experiment. 1. Heat 75 mL of water to 90 °C in a 250-mL beaker. 2. While the water is being heated, place 250 mg of salicylic acid, 1 drop of 85% phosphoric acid and 0.5 mL of acetic anhydride in a test tube. Add a boiling chip to the mixture and gently shake it in order to mix the reactants. 3. Heat the tube in the beaker of water at 85 - 90...
Question 1 Use a DRY 5 mL conical vial for the reaction A Serves as a catalyst for the reaction Add one drop of concentrated phosphoric acid to the reaction mixtureTo avod splashing and evaporation of solvents while heating -8) Heat the water bath to 50 deg C Cto avoid crystals passing underneath the paper and through the filter D. So that water will fully evaporate giving a purer product Add an air condensor to the conical vial E. To...
PREPARATION OF PHARMACEUTICALS - Fischer Esterification
Reactions
Q: Calculate the expected mass of both methyl salicylate and
aspirin assuming 100% yield.
EXPERIMENT7 PREPARATION OF PHARMACEUTICALS Fischer Esterification Reactions Almost 2500 years ago, physicians such as Hippocrates recommended that patients chew on the bark of the willow to alleviate pain. The active ingredient in willow bark was found to be salicin, a compound made of a molecule of salicyl alcohol bonded to a p-D-glucose molecule. In the stomach, the bond between...