Experiment 9 Preparation of Methyl Salicyclate H 2

Experiment 9: Preparation of Methyl Salicyclate

H 2 SO 4

Wintergreen (methyl salicylate) Gaultheria procumbens This tiny, North American plant of the heath family grows in pine forests and on humid ground with sphagnum. The Indians knew its effects, which is due to methyl salicylate. Like salicylic acid, it is analgesic and antipyretic. *bottle

Experimental setup: total reflux

Vacuum Distillation BP 222 °C at 100 k. Pa At what temperature will it boil at 10 k. Pa? P/k. Pa Rule of thumb: BP decreases by 10 °C each time the atm pressure decreases by ½. T/ C 100 22 50 210 25 200 12. 5 190 6. 3 180 3. 1 170 1. 6 160 0. 8 150 0. 4 140

How do I go about figuring out what my unknown is? 1. From your solubility measurements, you should be able to classify your unknowns according to the solubility classes discussed. 2. Look up some reference IR spectra in your manual that have the possible functional groups present in your unknown. 3. Look up some possible classification tests you can run to confirm their presence. 4. Complete and hand in your preliminary report if you haven’t done so. 5. Select a possible derivative based on the properties of the derivative. For example, choose a derivative that will allow you to distinguish between other possible compounds with melting points (± 5 C) or boiling points (± 10 C) within the value of your unknown

Classification Tests Classification test should only be run to confirm your suspicions regarding the presence of a functional group suggested by your solubility tests or IR. Always run a blank and a known at the same time you run your unknown so that you know what a positive test looks like and that you performed the classification test properly. Derivatives A derivative should be chosen whose melting temperature will allow you to differentiate between possible compounds. If you have a carboxylic acid or an amine, a titration can be substituted for a derivative providing that the molecular weights of other possible compounds in your possibility list can be excluded on the basis of your titration results.

What information can we deduce from this spectrum? 1718 cm-1 neat liquid

What information can we deduce from this spectrum? KBr disk

neat liquid

The following is a liquid hydrocarbon

The compound contains nitrogen

Compound contains C, H, O