Experiment 3'6C

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• Experiment 3.6C
• Miniscale Isolation of
• Caffeine from NoDoz

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Caffeine
1,3,7-trimethyl-2,6-dioxo-1,2,3,6-tetrahydropurine
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Caffeine

• Found in leaves, beans, and fruit of over 60
  plants (most in coffee beams and tea leaves)
• Acts as a natural pesticide for the plant
• Humans central nervous system stimulant
• The worlds most widely used psychoactive
  substance
• Overuse nervousness, irritability, anxiety,
  insomnia, headaches, heart palpitations

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Caffeine
Source Wikipedia, July 15, 2007
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Purpose

• Isolate caffeine from a complex matrix.
• Purify isolated caffeine.
• Quantify amount of caffeine recovered.
• Analyze the IR spectrum.

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Components of NoDoz

• Caffeine, inorganic binders
• Different physical properties

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Inorganic Binders, etc.

• Carnauba Wax
• Yellow 10 and 6
• Dextrose
• Hydroxypropyl methyl cellulose
• Magnesium stearate
• Microcrystalline cellulose
• Silicon dioxide
• Starch

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Procedural Overview

• Extraction (solid/liquid)
• Filtration
• Extraction (liquid/liquid)
• Recrystallization

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Miniscale Liquid-Liquid Extractionusing a
Separatory Funnel
Dont EVER point the sep funnel at another
person!!
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Pre-lab Preparation

• Read
• Expt. 3.6 background
• Expt. 3.6C (This is where your procedures will
  come from)
• Tech I How to do a Miniscale Extraction,
  (p. 76)
• Tech F recrystallization, gravity suction
  filtration
• Appendix C - Flowcharts

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Pre-lab Preparation

• Prepare Notebook
• Header information
• Purpose statement
• Reference (title, authors, edition, pages)
• Table of reagents
• structure, relevant physical properties,
  hazards of caffeine, methylene chloride and
  ethanol
• Procedures (two column format)
• Melting point will not be measured.
• Flow chart
• download and fill out, hand written
• Turn in at the beginning of class

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In Lab

• Follow your procedures to isolate the crude
  caffeine and recrystallize it.
• Remember to account for the following items
• Mass
• Actual caffeine in tablet (from manufacturer)
• NoDoz tablet
• Crude caffeine
• Recrystallized caffeine
• Volume
• Solvents used for extractions

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After Lab

• Calculations (in notebook after the Procedures)
• Weight actual caffeine in tablet
• crude caffeine recovered
• recovery during recrystallization
• recovery overall
• Results (following the Calculations)
• Download the IR spectrum of caffeine. Annotate it
  and turn in with datasheet. Does the spectrum
  lend support to the proposed structure? Explain.
• Write a few sentences summarizing your results.
  Did you achieve your objectives? How do you know?
  Also comment on the recovery overall and
  compare it to the manufacturers claim concerning
  the amount of caffeine in each tablet. How could
  you assess the purity of your crystals?

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Data Analysis

• Weight of actual caffeine in tablet (use label)
• crude caffeine recovered
• recovery during recrystallization
• recovery overall