To prepare aspirin, salicylic acid is reacted with an excess of acetic anhydride. A small amount of a strong acid is used as a catalyst which speeds up the reaction. In this experiment, sulfuric acid will be used as the catalyst. The excess acetic anhydride will be quenched (reacted) with the addition of water.
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What is the reaction to make aspirin?
Aspirin can be made by reacting salicylic acid with acetic acid in the presence of an acid catalyst. The phenol group on the salicylic acid forms an ester with the carboxyl group on the acetic acid. However, this reaction is slow and has a relatively low yield.
How aspirin is manufactured?
Aspirin is the most widely sold over-the-counter drug. The production process involves the reaction of Salicylic acid and acetic anhydride in glass lined vessels. The liquid produced is pumped to a crystallizer, where it is cooled down to start the crystallization to Aspirin.
What materials are used to make aspirin?
In particular, the production of hard aspirin tablets requires only four ingredients: the active ingredient (acetylsalicylic acid), corn starch, water, and a lubricant.
How is aspirin purified in a lab?
The mixture is heated to form the acetylsalicylic acid (C9H8O4) and acetic acid (C2H4O2). After the reaction takes place, water is added to destroy the excess acetic anhydride and cause the product to crystallize. The aspirin is then collected, purified by recrystallization, and its melting temperature measured.
Why is water added to synthesis of aspirin?
The excess acetic acid will be quenched with the addition of water. The aspirin product is not very soluble in water so the aspirin product will precipitate when water is added. The synthesis reaction of aspirin is shown below: Since acetic acid is very soluble in water, it is easily separated from the aspirin product.
What happens when aspirin reacts with water?
Aspirin (acetylsalicylic acid) reacts with water (such as water in body fluids) to give salicylic acid and acetic acid, as shown in Figure 5.2.
How can I make aspirin at home?
Where is aspirin manufactured?
Most of the North American supply of aspirin, for example, comes from China, which produces about 120 billion tablets per year. Other widely used drugs, such as omeprazole and simvastatin often come from Puerto Rico and India. Maybe this is no big deal.
How do you make aspirin in a school lab?
SYNTHESIS OF ASPIRIN (acetylsalicylic acid) Place 2.0 g (0.015 mole) of salicylic acid in a 125-mL Erlenmeyer flask. Add 5 mL (0.05 mole) of acetic anhydride, followed by 5 drops of conc. H2SO4 (use a dropper, H2SO4 is highly corrosive) and swirl the flask gently until the salicylic acid dissolves.
Is aspirin made from benzene?
In fact, the starting material for the chemical synthesis of aspirin is benzene, derived from petroleum. This is then converted to phenol which in turn is converted to salicylic acid which is then converted to acetylsalicylic acid or ASA, which we know as aspirin.
What is another name for aspirin?
Aspirin is a generic drug sometimes referred to as acetylsalicylic acid (ASA). It is an NSAID that treats inflammation and prevents the formation of blood clots.
Why is ethanol used to purify aspirin?
Ethanol has been chosen as the solvent because the polar nature of the hydroxyl group causes ethanol to dissolve many ionic compounds, moreover the ethanol molecule also has a non-polar end, and it will also dissolve non-polar substances. While cooling, crystallization takes place.
Why is sulfuric acid used in aspirin synthesis?
The purpose of adding sulphuric acid (catalyst) is to aid and augent the process of detaching the acetate ion (CH3COO–) from acetic anhydride which ultimately gets associated with H+ ion from phenolic hydroxy group in salicylic acid to be eliminated as a mole of acetic acid. Aim: To prepare aspirin from salicylic acid.
How is aspirin made and tested in industry?
Because today’s aspirin is mass produced in tablet form, Spectrophotometers are a reliable and economical way to keep the purity of Aspirin consistent throughout the manufacturing process. The purity and amount of acetylsalicylic acid in aspirin can be measured using a Visual Spectrophotometer.
Why is phosphoric acid used to make aspirin?
Phosphoric acid acts as a catalyst to accelerate the reaction. (Catalyst is a substance that can be added to a reaction and helps speed up the reaction without getting caught in the process.
What happens when aspirin reacts with vinegar?
If you have an old bottle of aspirin tablets you may find they have a slight smell of vinegar, especially if they have become damp. As you have seen, when aspirin reacts with water the carboxylic acid that it forms, by hydrolysis of the ester group, is acetic acid.
What happens when aspirin is boiled?
Aspirin is a pain reliever and fever reducer, but if it’s allowed to react with water then it can undergo hydrolysis, forming salicylic acid and acetic acid, which is no longer effective. This reaction can occur under acidic or basic conditions.
Why does aspirin smell like vinegar?
When acetylsalicylic acid ages, it may decompose and return to salicylic acid and acetic acid. If you have a very old bottle of aspirin around the house, open it and take a sniff. It may smell like vinegar, because vinegar is dilute acetic acid.
Is aspirin made from tree bark?
It is a common misconception that aspirin is found in the bark of the willow tree. A related compound called salicin does indeed occur in willow bark, thereby explaining the use of the bark as a medication since the time of Hippocrates.
What tree bark contains aspirin?
The bark of white willow contains salicin, which is a chemical similar to aspirin (acetylsalicylic acid).
What part of a willow tree is used to make aspirin?
Willow bark, the bark of several varieties of willow tree, has been used for centuries as a pain reliever. The active ingredient in the medicine made from willow bark is called salicin. Some people use willow bark as an alternative to aspirin, particularly those that experience chronic headaches or back pain.
Is aspirin synthetic or natural?
Yet, while aspirin has been one of the most popular pharmaceutical agents of the past one hundred years, it is actually a synthetic derivative of the natural substance salicylic acid—the associated healing properties of which have been known for millennia.
What was aspirin originally used for?
Originally used as an antipyretic and anti-inflammatory drug, aspirin then became, for its antiplatelet properties, a milestone in preventing cardiovascular and cerebrovascular diseases.
How do you make aspirin without acetic anhydride?
It is possible to produce aspirin by reacting salicylic acid with acetic acid & sodium acetate by heating one and half hr. & pouring the reaction mixture in ice-water mixture to get solid aspirin. I think the obvious answer here would be the use of acetyl chloride with some DMAP and base.