Extraction of Trimyristin from Nutmeg

Note: With consent, your experimental data may be used in a research presentation at the American Chemical Society national meeting. Please consider this when performing the experiment!

Read Standard Reflux on page 201 of “The Organic Chem Lab Survival Manual.”

Prelab Question 1: Trimyristin is a triglyceride. What are triglycerides? Prelab Question 2: How do microwaves heat?

Microwave Procedure:

ƒ Add approximately 2.5 g of ground nutmeg (record exact mass) and 15 mL of diethyl ether to microwave vessel. ƒ Cap microwave vessel as directed. (Monitor vessel capped differently.) ƒ Place all microwave vessels into Milestone Ethos laboratory microwave system as directed. (Monitor vessel is equipped with fiber optic temperature probe.) ƒ All vessels are heated according to the following temperature profile:

Step 1 Ramp from room temperature to 65°C in 1.5 min Step 2 Hold at 65°C for 5.5 min

Step 3 Vent (cooling) for 10 min

ƒ Allow vessels to cool below boiling point of ether before uncapping. (Ice bath can be used to speed up process.) ƒ Process microwave extract as directed with conventional extraction method.*

Traditional Extraction: Weigh approximately 2.5 g of finely ground nutmeg and combine it with 15 mL of diethyl ether in an appropriate round-bottom flask. Attach a water-cooled condenser to the vial and set the apparatus in an aluminum block on a hot plate. Gently heat the mixture under reflux for 45 minutes or more. *Filter the mixture by gravity. Wash the nutmeg residue in the filter paper with a small amount of ether, saving the filtrate. Evaporate the ether from the filtrate. Recrystallize the product from 95% ethanol. Allow the trimyristin to air dry. Weigh the product, report the percent recovery, and measure its melting point.

Data Collection:

In a document separate from your lab notebook, please submit a data table containing the following information:

Mass nutmeg Mass Recovery Melting point (g) extracted (%) range (all trials) trimyristin (g) (°C) Microwave Extraction Conventional Extraction

SAVE EXTRACTED MATERIAL!! Please place extracted trimyristin into labeled vials for potential further analysis by Dr. B.

Questions for Discussion:

ƒ How did the temperature of the conventional extraction (temperature of “reflux”) compare to the temperature of the microwave extraction? ƒ What is the boiling point of diethyl ether? How is it possible to surpass the boiling point? (Hint: the microwave uses a closed system.) ƒ Rationalize why the microwave extraction required only 7 minutes while the conventional extraction required 45 minutes. ƒ Trimyristin comprises approximately 30% of the mass of nutmeg? How accurate are your results? ƒ In your opinion, which extraction method is “better”? Why?