Format lab report

03/30/2021

Synthesis of Isopentyl Acetate (Banana Oil)

Introduction:

Easter is mostly found in fats, oils, and low molecular weight easters will be most likely in fragrances and things that have flavors. Moreover, to synthesize easter it would be much easier using the Fisher esterification. In this experiment, we will be synthesizing isopentyl acetate using esterification reaction between acetic acid and isopentyl alcohol. Also, in the reaction part of this lab we will be adding concentrated sulfuric acid to initiate the reaction. To explain more, we will be staring with part reaction and then we will be doing the extraction part. However, we did not do the distillation for this experiment. The idea that in order to synthesize easter we have to convert carboxylic acids in presence of alcohol with a strong catalyst.

Procedure:

Day One:

Reaction:

1-Assemble a reflux apparatus using a 100 mL of round bottom-flask with a magnetic stirring, Claisen Head, thermometer and a water condenser.

2-Using a heating mantle as the heat source and a magnetic stir plate for stirring.

3-Add 5.0 mL of isopentyl alcohol to the 100 mL flask.

4-Add 7.0 mL of acetic acid to the 100 mL flask.

5-Carefully add 5 drops of concentrated sulfuric acid to the round-bottom flask in a dropwise fashion using a pipette. NOTE: It is very important to add the reagents in the PROPER order.

6-Reattach the condenser and turn on the water to circulate through the condenser.

7-Heat the solution to reflux (ca. 110 C) and then hold at reflux for 60 minutes.

8-After refluxing, remove the heat source and allow the apparatus to cool to almost room temperature.

Extraction:

1-Add 10 mL of diethyl ether to the 100 mL flask. Stir well.

2- Add 10 mL of water to the 100 mL flask. Stir well.

3-Transfer the mixture to a separatory funnel and allow the layers to separate.

4-Drain off the lower acidic aqueous layer and set aside.

5-Carefully, add approximately 10 mL of 5% sodium bicarbonate to the separatory funnel slowly. NOTE: you will observe some gas bubbles (CO2(g)).

6-Mix the layers well in the separatory funnel and then allow them to separate.

7-Drain off the lower aqueous layer and set aside. DO not combine with the aqueous layer from step 4. The acidic layer from step 4 will react with the basic layer from this step to form CO2(g).

8-Wash the upper organic layer a 2nd time with 10 mL of 5% sodium bicarbonate. Mix the layers well and allow them to separate.

9-Drain off the lower aqueous layer and combine with the aqueous layer from step 7.

10-Drain off the upper organic layer into a clean Erlenmeyer flask.

11-Add a small amount of anhydrous sodium sulfate (0.5-1.0 g) to the organic layer and swirl well to remove any remaining water.

12-Decant the organic layer into a pre-weighted 100 mL RB flask.

13- Remove the ether solvent on the rotavapor. Do not allow the water bath in the rotavapor to get above 30 C or you will lose product.

14-Weight the product and calculate the percent yield of the crude product.

15-Dispose of the aqueous layers from step 4,7, and 9 in the aqueous waste container.

Day Two:

Distillation:

1-Set up a simple distillation using a magnetic stir for stirring and a heating mantle for heating. Be sure to have a magnetic stirrer in you flask with your crude product from Day one.

2-With good stirring and gentle heating gradually heat the reaction flask until your product begins to boil while observing the distillation temperature as it rises.

3-At first a “forecut” will be collected of lower boiling (<140 C) impurities in your product. Collect the forecut in a small “pre-weighted” Erlenmeyer flask. Report the amount of forecut that was taken.

4-When the distillation temperature reaches 140 C, collect your product in a clean “pre-weighted” Erlenmeyer flask. Continue distilling until only 1-2 drops of liquid remains in the distilling flask. Record the observed boiling point range in your notebook.

5-Obtiain a weight of your distillated product and report the percent yield.

6-Obtain an IR spectra of your product using a salt plates identify the following peaks on the IR (C=O,C-H,C-O). is any acetic acid detected (O-H) peaks?

Results:

Product	Amount
Sodium Sulfate	1 g
Pre-weight RBF	78.38g
Weighted RBF + Product	92.03 g

*Theoretical yield =

-13.65g isopentyl alcohol * 1mol/88.1g * 1mole product/1 mol reactant * 130.2g/1 mol isopentyl acetate= 20.17g isopentyl acetate.

% yield= (13.65g/20.17g)*100= 67.7%

Discussion:

Based on my results that I have got for this experiment it is shown that I have fair percent yield. It relates to the objective for the idea that is percent yield to see the manufacture products for this synthesized lab. Using the esterification reaction we synthesize isopentyl acetate from acetic acid and isopentyl alcohol via reflux and distillation.

Conclusion:

We have used a many techniques in this lab to synthesized isopentyl acetate such as reflux, distillation and extraction. We synthesized easter to use it in the real world because it has a good smell and it appears to be found in the nature. By now, I know how does easter synthesized and what is the purpose of doing it.