Question

Synthesis of Aspirin Experiment

1. What type of reaction is formation of Aspirin? Can this reaction be performed using acetic acid instead of acetic anhydride? If so, what are advantages/disadvantages of using acetic acid?
2. What is difference between salicylic acid vsacetyl salicylic acid for human consumption?
3. Role and significance of acetic anhydride in this reaction – chemistry aspects

Answer 1

1.

Aspirin ( also called acetyl salicylic acid ) is a chemical species , formed from salicylic acid and acetic anhydride in presence of an acid to form a ester , the reaction is type of esterification reaction , as an ester group is formed.

Even the reaction can also be called as acetylation reaction , since a acetyl group is formed .

The reaction for the formation of ester is -

Aspirin can also be prepared from reaction of salicylic acid and acetic acid , instead of acetic anhydride , as -

The reaction of salicylic acid with acetic acid yields aspirin , but the yield is very low, as water is produced , which hydrolysis the ester back ,

So, in order to avoid this situation , acetic anhydride is used , which is cheap , and gives higher yield.

2.

The difference between salicylic acid and aspirin is as follows -

Salicylic acid -

• As per to IUPAC , salicylic acid is named as , 2 – hydroxy benzoic acid.

• Salicylic acid , is one the key ingredients in many skincare products , for the treatment of acne , dandruff ,psoriasis , warts , corns etc .

• Salicylic acid removes the outer layer of the skin , and thereby treats issues like acne , dandruff , psoriasis etc.

Aspirin -

• As per IUPAC , Aspirin is named as , 2 – acetoxy benzoic acid.

• Aspirin , is commonly used for the treatment of pain , fever or inflammation . Hence, is a analgesic ( drug use to reduces pain ) and antipyretic ( drug use to reduce or prevent fever ).

• Aspirin intake also reduces the chances of cancer , like colorectal cancer .

• Aspirin intake immediately after a heart attack , reduces the chances of death .

3.

Significance of acetic anhydride in the reaction of the formation of aspirin -

Acetic anhydride is a strong reagent , which avoid the reaction to go back into respective reactants ,

And the reaction of salicylic acid with acetic anhydride does not produce water as a by product , which can again hydrolyse the ester ( aspirin )back .

Therefore , the reaction of salicylic acid with acetic anhydride produces a higher yield of aspirin .