Chemistry 102 Intro. GOB Chemistry
ASPIRIN SYNTHESIS & ANALYSIS
Introduction:
Your team is employed by the Generic Pharmaceutical Corp. in their consumer
products lab. Your job is to find and test a synthesis procedure for acetylsalicylic
acid (aspirin). Further, your team is to analyze the product for salicylic
acid in a controlled, quantitative procedure, if possible. While this is
the active ingredient in aspirin's analgesic, antipyretic and anti-inflammatory
properties, this is also responsible for the irritation and possible hemorrhaging
of the mouth, esophagus and stomach as aspirin passes through them before
being absorbed in the intestine. Obviously we want our product to have
little or no detectable amounts of salicylic acid.
In addition, the marketing department will need to know the theoretical
and actual yield of aspirin in your process. They will need to know the
quantities of each reagent used, and how to minimize their amounts without
compromising yield. You only have a week to do experiments before the management
wants a progress report, so please consult with other teams to coordinate
your work.
Objectives:
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To synthesize aspirin as economically as possible.
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To determine the purity and the theoretical and actual % yield, and suggest
ways to improve them.
The following are some hints and questions to guide your work. They are
not inclusive; so you are encouraged, and indeed, expected to follow your
own ideas, as long as you consider safety issues.
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How will you find a procedure for making aspirin? If more than one are
found, how will you decide which is better for our purposes?
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How will you determine the % yield in your procedure?
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How many preparations will need to be done to ensure accurate and reproducible
yields? (Given our R&D budget constraints, each team will be limited
to one preparation per person.)
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How will you detect salicylic acid in your aspirin preparation?
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Can you do a standardized test to determine the amount of salicylic acid
contamination?
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What might cause errors in your analysis? How could you eliminate or minimize
them?
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Can you determine the minimum amount of each reagent needed to produce
the best yield?
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Does minimization increase or decrease salicylic acid contamination?
Materials:
You will have standard reagents and equipment available. Use the minimum
amount you think you might need, and get more, if necessary. Do Not
return unused portions to the stock bottles! Why not? We have samples of
competitors' aspirin tablets, pure acetylsalicylic acid and salicylic acid
for controls. Your team will need to ask for other reagents you may
need for the synthesis and analysis. Your team will rotate the
positions assigned for the prior project, with the assistant leader moving
up to leader and the leader becoming the data specialist. As this is a
high priority project, you have two weeks before the final report is due
to the management. Good luck!