Laboratory Reference Manual, Chemistry 201/202
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Experiment 3   Synthesis of Salicylic Acid from Oil of Wintergreen (Methyl Salicylate)

OVERVIEW | BACKGROUND | PROCEDURE | NOTES | REPORT

Report

The remaining experiments in Chem 201/202 are described by reports that mimic the style of writing used by organic chemists in research publications. A broad view of what is involved, and also detail instructions for each individual item, can be found in the appendix How to Write Lab Reports.

Because some of the writing conventions used in organic chemistry will seem strange (the passive voice, the repetition of some information, but not all, etc.), we have provided sample reports for you to study and learn from. Use the language and organization of the sample report everywhere you can. At the same time, be faithful to the details of your experiment so replace everything in the sample report that needs replacing.

Once you have developed an electronic version of your lab report, do not share it with classmates. All individuals are expected to produce their own reports.

Filing the report: As before, reports must be filed electronically as PDF files. Name the PDF file email_prefix SalAcid day.pdf.

Email the file to your lab TA by 6 PM, Monday, Oct 8.

Monday lab: aremmel@reed.edu
Tuesday lab: emurphy@reed.edu
Thursday lab: lkrause@reed.edu
Friday lab: ikirby@reed.edu

Late reports will be accepted up to 5 days after the due date (Oct 13), but the report portion will be marked 'unsatisfactory'. This is a far better outcome than 'no credit'.

Organizing your PDF file: Page 1 should begin with your report (see Sample Report that follows). Follow this with the anwers to the Abstract Exercise (see below) and then a scan of your notebook.

 

Sample Report

Synthesis of Benzoic Acid from Methyl Benzoate

J. Kroger

Tuesday, BigJohn@reed.edu

Abstract
Benzoic acid was obtained in 78% yield by refluxing methyl benzoate with NaOH. The product was identified by its melting point.

Results and Discussion
Salicylic acid was obtained in 78% yield by refluxing methyl salicylate with aqueous NaOH. Recrystallization of the acid gave white needles, m.p. 121-122.5 oC (lit. 118 oC [1]).

Experimental
Preparation of benzoic acid. Methyl benzoate (4 mL, 33 mmol) and 1 M aq. NaOH (10 mL, 20 mmol) were refluxed for 30 min. The solution was acidified with 66 M aq. H2SO4 (~25 mL) and filtered. The crude product was recrystallized from boiling ether and dried for three weeks to give kelly green crystals of benzoic acid: 3.33 g (78% from methyl benzoate), m.p. 121-122.5 oC (lit. 118 oC [1]).

References
1. Renn, S., ed. "Suzy's Super Big Book of Chemicals", 1st Ed., XYZ Press, New York, 1984.

E-factor
This experiment used the following materials: methyl benzoate (3 g), NaOH (3 g), sulfuric acid (4 g), ethanol (40 g); total consumables (50 g). The product (3.33 g) does not count as waste; total disposables (46.7 g). E-factor = 14.

Abstract Exercise:
Attach the title and abstract from a recently published article in the Journal of Organic Chemistry to your report (its ok to use copy-and-paste). The journal is available online through the Reed library's web site. Any article of any length will do so long as the title and abstract both mention the synthesis of an organic molecule ("synthesis" or "preparation" should probably appear in the article's title, and one of these words must appear in the abstract).

1. Cite the article and give its DOI number
2. Underline a sentence in the abstract that describes the preparation of an organic compound
3. Draw a chemical equation that describes the experiment used to prepare the substance listed in #2. In other words, find the experiment that produced this compound, draw the starting material(s), the reagents and important reaction conditions (reagents, temperature, time, solvent), and the product.
4. In just one or two sentences, describe what information about this experiment has been omitted in the abstract. In other words, I expect the sentence in #2 to provide less information than the drawing in #3 (or the description of the experiment that you find in the article). How do they differ?


OVERVIEW | BACKGROUND | PROCEDURE | NOTES | REPORT

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