To start the lab, turn the hot plate on (225 °C) and weight out nutmeg (1.002 g) into a microscale round-bottom flask (RBF). To the RBF, add tert-butyl methyl ether (TBME 3 mL) and 2-3 boiling chips. Attach the black plastic connector to the RBF as well as the air condensor column. Using the three-prong clamp, lower the RBF into its appropriate hot well on the aluminum block of the hot plate and allow the mixture to gently boil. If the solution boils too violently, lift it up slightly out of the aluminum block to avoid bumping. After 10 min, remove the flask from the heat and allow the solids to settle at the bottom of the RBF. While the solid settles, set up a microscale filtration system using a glass pipet and small wad of cotton. Below the pipet, place a tarred Erlenmeyer flask. With a clean pipet, remove the solution from the RBF, holding the RBF at a slight angle, and allow the liquid to drain through the filtration apparatus. If the solution becomes stuck in the filtration system, attach a pipet bulb to the top of the filtration pipet and gently squeeze it to create pressure. Be sure to remove the pipet bulb before releasing the pressure on it. After all the liquid has been filtered, add TBME (2 mL) to the RBF and warm briefly (2-3 min) with the column reattached. Again, let the solids settle and filter the solution as done previously. In the fume hood, warm the filtered solution in the Erlenmeyer flask using body temperature and pass air over the top to evaporate off the TBME. The resulting solid will be crude trimyristin. After letting the crude trimyristin to dry (5 min), determine its mass (0.484 g). For every 100 mg of crude product, use 1 mL of acetone during recrystallization. During the first recrystallization of crude trimyristin, acetone (5 mL) was used as the solvent. The resulting crystals were white and powdery. The melting point (54-55 °C) and mass (0.163 g) of the first recrystallized trimyristin. For the hydrolysis of trimyristin, set aside some of the first recrystallized trimyristin (0.061 g) into a clean RBF. To the flask add NaOH (2 mL, 6 M), ethanol (2 mL, 95%) and boiling chips. For 45 minutes, reflux the solution on the hot plate (250 °C). While the hydrolysis is being refluxed, perform a second recrystallization using the remaining trimyristin (0.102 g) with the same methods as before. The final mass (0.066 g) and melting point (57 °C) of the second recrystallized produce was determined. When the 45 minutes of refluxing was a complete, allow the solution to cool in the RBF to room temperature (rt). Once cooled, add the solution to a 50 mL beaker containing water (8 mL) then drop-wise add HCl (2 mL, 6 M). The addition of HCl should cause myristic acid to precipitate out. If a gelatinous solid forms, the mixture needs to be stirred more and more HCl should be added if it does not break up. On ice, cool the beaker for 10 min with stirring. Using a vacuum filtration, collect the solid and wash it three times with ice cold water. Allow the solid myristic acid to dry at least overnight the determine the melting point (54 °C) and mass (0.035 g).
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