Extraction of Eugenol from Cloves Oil

Isolation of Acetyleugenol (garlic clove Oil) from Cloves Purpose In this experiment, you allow obtain the indwelling cover from cloves by steam distillation. You pull up stakes then divulge a component (acetyleugenol) from the oil by liquid-liquid distillion. Finally, you will discriminate the acetyleugenol by employ a rotovap for reduced pres for sure distillation, which will finish the extreme sol ventilate (dichloromethane). undercoat Whole cloves contain between 14% and 20% by weight of essential oils, but only half of that bear be isolated as acetyleugenol. Clove oil contains two basic compounds eugenol and acetyleugenol.As a result of Daltons Law and Raoults Law, both of these substances thunder mug be take away from the cloves with a steam distillation. Eugenol is polar repayable to the erosiveic hydroxyl (OH) group, but acetyleugenol is non polar. As a result, they can be separated by extraction from a 5% sedimentary NaOH result. Acetyleugenol will evapor ate in the organic CH2Cl2 storey, while eugenol carcass in the aqueous infantry layer as a phenoxide. This can be seen in the reaction below (where ArOH is eugenol), because dissolve ions prefer the aqueous phase. ArOH(aq) + OH-(aq) ? ArO-(aq) + H2O(Liq)Acetyleugenol has no acid proton, and cannot ionize. So, it prefers the organic phase. Essential oils from plant materials atomic number 18 used today for medicinal and some other purposes. Among these oils are camphor, quinine, oil of cloves, cedarwood, turpentine, cinnamon, gum benzoin, and myrrh. The U. S. FDA has say clove oil to be the some effective remedy for a toothache. Substances 25 g whole cloves (350 g per testing ground section) 100 ml DI water (1. 5 L per lab section) 10 ml 5% NaOH (150 ml per lab section) 45 ml CH2Cl2 (650 ml per lab section) Mg SO4 or Na2SO4 (anhydrous) Apparatus Items in outfit 50-ml round- seated flask distillation transport thermometer adapter large stupid optical condenser Claisen adapt er 125-ml separatory move Items not in kit Plastic move 100-ml graduate cylinder stands and clamps aluminum intersect thaw mantle (for 250-ml flask) 250-ml separatory funnel shape shape 125-ml Erlenmeyer flask w/ stopper Rotovap Procedure 1. brand 25 g of whole cloves in a 250-ml round-bottomeded flask, and number 100 ml of DI H2O. A plastic funnel can be used if necessary to air the cloves into the flask. 2. Set up a well-clamped unprejudiced distillation apparatus with the large bore condenser.Insert a Claisen adapter with a 125-ml separatory funnel between the flask and the distillation head, alike(p) to Fig. 23. 4 of Zubrick. Ensure the valve on the separatory funnel is closed. Then cover the flask, distillation head, and the bottom of the heating mantle with aluminum foil to insulate for a faster distillation rate. 3. Collect 60 ml of distillate. Also, concurrently heat distilled water to 90oC on a hot plate for addition in step 4. 4. Add 60 ml of hot H2O to the sep aratory funnel, then return the stopcock to add the water to the flask. Be sure to complete stopper from funnel before opening its valve.Also, be sure to close the valve after adding the water. 5. Collect other 60 ml of distillate. 6. Add 10 ml of 5% NaOH solution to the distillate to neutralize (deprotonate) the eugenol. 7. Acetyleugenol is not very disintegrable in H2O, and is easily extracted from the distillate with CH2Cl2. bit the 130 ml of distillate solution in a 250-ml separatory funnel and remove the acetyleugenol with three 15-ml portions of CH2Cl2. Gently trembling the separatory funnel will fail to remove the acetyleugenol, hitherto vigorous shaking will nonplus a boundary layer that is a visible organic- aqueous emulsion.Therefore, shake vigorously, and remove the lower layer up to, and not including, the emulsion. Caution -Pressure typically builds inside separatory funnel when shaken Be sure to vent stopcock frequently while shaking Do not vent towards yoursel f or any other individual 8. connect the CH2Cl2 extracts in a 125-ml Erlenmeyer flask and add just enough anhydrous magnesium sulfate or sodium sulfate (drying agents) so that the solid no continuing clumps together. Stopper the flask, and let stand 5 minutes. (Note that stopper size is printed on the flask. ) 9.Decant the organic solution into a weighed 250- or 500-ml round-bottom flask. Leave solid drying agent behind. 10. With the instructors assistance, evaporate the solvent with the rotovap to isolate the liquid acetyleugenol. Obtain product mass. exorbitance Disposal The used cloves can be discarded in the trash. The aqueous shove along can be neutralized, and then emptied into the sink. Place used drying agent in the dissipation fluff up. Lab techs will place stash away solvent from the rotovap in the waste jar as well. Recommended Reading Small home plate Syntheses, pp 25-26 (steam distillation) and 28-29 (extraction).McMurry, J. , Organic Chemistry, pg 626 in 8e, or pg 603 in 7e (phenoxides). Zubrick, J. W. , The Organic Chem Lab Survivor Manual, sixth Ed, pp 183-7 (steam dist), 196-9 (rotovap) and 321-2 (steam dist theory). www. chemfinder. com en. wikipedia. org/wiki/Clove Data To Collect coiffure mass of Acetyleugenol after evaporating the solvent in the rotovap. Theoretical Yield Basis try out background section for maximum getable quantity. Actual Yield Basis constitution the find mass divided by the theoretical yield. Also report recovered mass divided by the sign mass of cloves.For the compounds isolated section, find opinionated names, as well as tabulated MPs and BPs, for both compounds. Post-Lab Qs 1. wherefore is eugenol soluble in aqueous base while acetyleugenol is not? (Hint McMurry describes some crucial properties of phenols) 2. How can the eugenol be separated from the aqueous base layer? (after the acetyleugenol has been removed) 3. What properties of clove oil make it an effective remedy for a toothache? 4. How do es steam distillation extract water-insoluble oils from the cloves? (Hint What do Daltons Law and Raoults Law tell us? ) 5. How does the rotovap berth?