Trimyristin Synthesis Lab Report

Isolation of Trimyristin from Nutmeg and Its Hydrolysis to Myristic Acid Compounds having complex molecular structures can be separated from natural materials. Usually they are components of very complex mixtures. To obtain pure compounds, long, tedious separation and purification procedures are often required. The triester, trimyristin, is however an exception and can be extracted from ground nutmeg seeds with tert-butyl methyl ether. Crystallization from acetone yields the pure compound. Most of the numerous other ether soluble components of nutmeg remain in the acetone solution. Note that triesters of glycerol, such as trimyristin, in which the carboxylic acid portion of the molecule is unbranched and contains 14 or more carbon atoms, are…show more content…
Then again, while leaving behind as much solid as possible, transfer as much liquid as possible into a pressure filtration assembly (p. 68 lab text) and filter the liquid into a clean, dry, tared 25 mL Erlenmeyer flask (tared = weighed empty). Be sure that the filter assembly is resting in the flask prior to transferring the liquid, as some liquid will filter through immediately. The filtration apparatus is made by pushing the micro Buchner funnel (polyethylene frit in place - no filter paper) into the end of a plastic pipet which has had the tip cut off and which has had a small hole cut into the squeeze bulb). Allow most of the liquid to filter by gravity, then, while holding your thumb over the hole in the squeeze bulb, gently apply pressure to complete the filtration. Care must be taken when squeezing the pipet bulb on the filter pipet. Too much pressure might cause the filter to leak or fall off. Add about 2 mL of fresh tert-butyl methyl ether to the solid in the RB flask, warm briefly, let the solids settle for a minute, and pipet the liquid to the centrifuge tube as before. Again allow the solids to settle briefly in the centrifuge tube, then filter the liquid through the pressure filtration apparatus, into the same 25 mL Erlenmeyer flask. Doing a rinse such as this helps to ensure that any trimyristin that was left behind in the RB flask and centrifuge tube is not lost, thereby helping to ensure that…show more content…
Compare the MPs of the once recrystallized and the twice recrystallized trimyristin. After the hydrolysis has proceeded for 45 minutes, allow the flask to cool to RT and pour the contents into a 50 mL beaker containing 8 mL of water. Carefully, in the hood, add dropwise with stirring, 2 mL of concentrated HCl (caution: corrosive liquid/noxious vapors). Myristic acid should precipitate. Cool the beaker in ice water for 10 min, with stirring, and collect the solid by vacuum filtration on a small Hirsch funnel. Rinse with three small portions of water, by breaking the vacuum, adding just enough water to cover the solid, and reapplying the vacuum as before. Filtration of the fine crystals is slow. Using too much rinse water will slow the process considerably. Allow the solid to dry at least overnight, weigh it, take a MP, and calculate the % yield. WASTE: Place all liquid wastes into the "Organic Liquid Waste" container. BEFORE YOU LEAVE THE LAB: turn off the sand bath, Mel-Temp, air and vacuum, put away your equipment and lock your drawer, clean up your work areas, close the fume hood sash completely and ask your TA for her or his signature. If you see caps off of bottles, replace the caps. If you see spilled chemicals, clean them up or at least report it to your TA. Summary of Results. Record the weight of trimyristin at all stages of the experiment. Report the following: (1), % recovery of crude and