Aspirin

Microscale Synthesis of Acetylsalicylic Acid

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Introduction:
Acetylsalicylic acid is a wonder drug par excellence. It is widely used as an analgesic (pain reliever) and fever depressant. It also reduces inflammation and may even prevent heart attacks. It has a few side effects for some people, yet it is safe enough to be sold without a prescription. Because it is easy to prepare, aspirin is one of the most inexpensive drugs available. It is produced in vast amounts. In fact, industry makes 43,000,000 pounds of the drug every year. This microscale experiment will permit you to make an amount of aspirin equivalent to about 1/2 of that found in an aspirin tablet.

Purpose: To synthesize acetylsalicylic acid on a microscale basis.

Equipment / Materials:
|salicylic acid |filter paper |

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|acetic anhydride |hot water |

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|conc. phosphoric acid |ice |

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|boiling chips |eyedropper |

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|microscale kit |2 beakers |

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|thermometer | |

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Safety:
Wear goggles at all times in the lab. The product is aspirin, but do not ingest it. It contains a lot of other dangerous chemicals, too. Phosphoric acid is very dangerous, handle it with care.
Procedure:
1. Accurately weigh out 135 - 140 mg. of salicylic acid and place it in a test tube from the microscale kit. Add a boiling