Organic Chemistry 333L, section 03M LaboratoryPre-LabAcid Catalyzed EsterificationBy: Cameron Kahn29 October 201314 January 2019TA: James CollieObjectives:In this lab, one will learn to synthesis an ester from an unknown alcohol by means of an acid catalyzed esterification. He/she will purify the product by means of distillation. Finally, one will record any data and determine the boiling point.Theory:In general, esters have a low molecular weight and often have a pleasant aroma. Because of thesefactors, esters are used in the food industry as artificial flavors and in the perfume industry as fragrances (Handy). The synthesis of esters is very important to both industries in particular. Esters can be prepared through a reaction of carboxylic acid with the presence of an alcohol. Theacid catalyzed conversion between the carboxylic acid and alcohol to form an ester is called Fischer Esterification (Fischer Esterification). This reaction can be done in reverse but still be slow. This cannot be said about the acetic anhydride ester synthesis. During the acid/base extraction, sodium bicarbonate is used to neutralize the acid. Once added, the sodium bicarbonate will form carbon dioxide which will in turn cause pressure build up in the apparatus. Throughout the esterification he/she will need to vent the apparatus often. Lastly, the use of micro boiling point techniques will determine the boiling point. This technique is used when there is only a small amount of liquid left; about 2~3 mL of desired product from the reaction.1 | P a g eMechanism: (As noted in the Chemistry 333 lab manual written by George Handy)Step 1.Step 2.Step 3.2 | P a g eProcedure:Start by setting up a 25 mL round bottom flask equipped with a reflux condenser apparatus (Handy). Lightly grease all glass connections and then sink the round bottom flask into the heating mantle. Next he/she will add 15 mL of acetic acid, 1.5 mL of concentrated sulfuric acid, and 2 mL of unknown alcohol to the 25 mL round bottom flask. Set the Variac between 70 and 75 and heat until the mixture begins to boil under the reflux. Then lower the Variac setting after boiling begins. Allow the solution to boil for 1.5 hours. Once the time is up, allow the flask to cool to room temperature. Place the contents from the round bottom flask into a separator funnel that has 12 mL of water. Rinse the flask with 12 mL of ether and pour it into the separator funnel.Shake thoroughly and discard the lower layer. Place 7 mL of water and 7 mL of saturated sodiumbicarbonate solution into the separator funnel. Shake and discard the lower aqueous layer. Then rinse organic layer using 10 mL of saturated sodium chloride solution (Handy). Transfer remaining layer into an Erlenmeyer flask. Add a micro-scoop of anhydrous magnesium sulfate and swirl for one minute. Let the product settle for 2-3 minutes. Transfer the dry supernatant ether solution to a clean 25 mL flask. Set up a short path distillation apparatus and heat strongly with a Variac setting of 65-70. Collect the product in a small test tube and determine the boiling point of the purified ester using a micro-boiling point. Perform a P-NMR analysis of final ester to determine the starting alcohol, and also an IR analysis.To perform a micro boiling point determination on a desired product, start by taking a small amount of the sample and pour it into a clean dry test tube. Next, obtain a small melting point capillary tube and place it into the liquid filled test tube making sure closed side up. Now take 3 | P a g ethe test tube and rubber band the thermometer to ensure the bottom of your test tube is at the same level as your thermometer bulb. Next, one will place the entire assembly into an extra-largetest tube filled with mineral oil so that the entire level of the liquid is below that of the mineral oil bath (Handy). Using the heating mantle, heat the mineral oil bath until it starts to bubble and gas begins to escape from the bottom of the capillary tube. The next step after one notices a steady stream of bubbles from the bottom end, remove the extra-large test tube from the heat source and allow the apparatus to cool. While the liquid cools, the atmospheric pressure will equal the vapor pressure of the liquid and the liquid will begin to rise up the capillary tube (Handy). Record your temperature as this will be the boiling point.Apparatus:Figure 1: Ring Stand (Handy)4 | P a g eFigure 2: Suction Funnel (Handy)Reagent Table:Name StructureMolecular Weight (g/mol)Melting Point (oC)Boiling Point (oC)Density (g/mL)Acetic AcidC2H4O260.05 16.6 118 1.05Diethyl EtherC4H10O74.1224 -116 34.6 0.706Magnesium SulfateMgSO4120.3626 1124 - 2.66Sodium BicarbonateNaHCO384.001 801 1413 1.03Sulfuric H2SO498.07 3 290 1.845 | P a g eAcidSodium ChlorideNaCl 58.442 801 1413 2.1651-ButanolC4H10O74.12 -90 1110.811-PropanolC3H7OH60.11 -126.5 97 0.804Name StructureMolecular Weight (g/mol)Melting Point (oC)Boiling Point (oC)Density (g/mL)IsopropanolC3H7OH60.11 -89.5 82 0.785N-HexanolC6H13OH102.18 -52 157 0.8141-OctanolC8H18O130.14 -15 196 0.827Disposal:Dispose of any gloves used during the experiment in the designated container. Dispose of all ester synthesized, in the organic waste container. Organic solvents (ether) should be disposed of in a different organic waste container than the ester. Any broken glass must go in the glass container and one should alert the TA. Wash excess aqueous solutions down the drain. For other general waste, talk to the TA for advice on proper disposal techniques. References:Ali, George Handy and Salman. Chemistry 333 & 334 Laboratory Manual. Columbia South Carolina: QDE Press, 2012.6 | P a g e"Fischer EsterificationFischer-Speier Esterification." Fischer Esterification. N.p., n.d. Web. 27 Oct. 20137 | P a g