Experiment 6 Isolation of Trinyristin from Nutmeg and Preparation of Myristic Acid from Trimyristin by Hydrolysis PDF

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Isolation of Trimyristin from Nutmeg and Preparation of Myrtsric acid From Trimyristin by Hydrolysis Dennis Rossi and Roger Mendez CHM 2210L TA: Suzeeta Bhandari February 26, 2019

Introduction Natural product chemistry is the isolation or organic compounds from living organisms. These isolations can be difficult because there are often many compounds within organisms because it becomes tough when trying to isolate a certain compound from a bunch of organic compounds extracted from a living organism. Nutmeg is an organic spice that is used all the time to extract trimyristin. Since trimyristin is approximately 25-40% of the weight of nutmeg. It is separated by solid-liquid extraction. Once the trimyristin is isolated, it will then be purified by recrystallizing. The crude material will be dissolved by a warm solvent and then let cool and dry. When a strong base is added to a triglyceride, the ester bonds are hydrolyzed and fatty acid salts are produced. Mixing two compounds into a 50:50 ratio and find the melting point. This is done because both compounds have the same melting points. It is done to to determine if the desired compound formed at the end of the experiment. A pure compound will melt with a high and sharp boiling point, and an impure compound will have a low and broad melting point. A 50:50 mixture will behave exactly like that. Reaction mechanism:

The push arrows for this mechanism was not able to be provided. The mechanism shows trimystrin racting with 3 NaOH/C2H2OH to form sodium mystric and glycerole. Then an acid (HCl) is added that

way the H proton from the HCl bond with the O- , forming mystric acid and NaCl. The NaCl is a by product. Side chain:

Experimental Section Part I: Isolation of Trimyristin From Nutmeg

A steam bath was started

0.2g nutmeg was put into a 50mL flask

The solvent was removed by evaporation

The solvent was weighed and then dried in a watch glass

6-8 mL of diethyl ether was put into same flask

The pipet was rinsed with 0.5 mL ether

The mixture of nutmeg was funneled into the pipet

Stirred for 15 min and a Pasteur pipet was prepared

The pipet was clamped over a 25 mL vacuum flask

Part I.b: Recrystallization Approx. 1 mL acetone was added to the solid

It was dissolved by gentle heating

The crystals were collected by suction filtration

It was cooled to room temperature

The crystals were weighed and recorded

Part II: Preparation of Mystric Acid from Trimyristin by Hydrolysis

0.2g trimyristin was put into a 10mL vial

The pH check was skipped

2mL of ethanol was added to the viral

It was shacked vigorously

3 boiling stones were added then swirled

The mixture was poured into a beaker with 10 mL cold HCl

The mixture was refluxed for 1 hour

The mixture was removed and allowed to cool to room temperature

The solid was collected by vacuum filtration

The crude was transferred into a test tube with petroleum ether

The mystric acid solution was collected from the test tube

It was dried then weighed and recorded

The solvent was evaporated using a steam bath

It then recrystallized

The oil present in the steam bath was placed in to an ice bath

Table of Contents Molar

Melting Boiling

Mass

Point

Trimyristin

(g/mol) 723.16

(Co) 56-58

Diethyl

46.069

-141

Ether

point (Co)

Chemical

Structure (organic style)

Density

Formula

(g/cm2)

311

C45H86O6

0.726

-24

C4H10O

0.713

Anhydrous

142.04

884

1429

Na2SO4

2.66

Acetone

58,08

-95

56

C3H6O

0.784

Ethanol

46.07

-114.1

78.37

C2H5OH

0.789

Sodium

39.997

318

1388

NaOH

2.13

36.46

Concen

Concentrati

HCl

tration

on

Depend

Dependent

ent 52-54

250.5

Sodium Sulfate

Hydroxide Hydrochlor ic Acid

Myristic Acid

228.370

1.2

C14H28O2

0.862

9

Trimyristin

Diethyl Ether



No hazards



Extremely flammable



Avoid contact with skin and eyes



Harmful if swallowed



Do not breath



May cause respiratory irritation



Keep container tightly closed in well-



May cause drowsiness or dizziness

ventilated place



May cause damage to organs



Keep away from heat



Keep container tightly closed in well-

Anhydrous Sodium Sulfate 

Toxic to aquatic life



Keep container tightly closed in wellventilated place

Ethanol

ventilated place Acetone 

Highly flammable



Highly Flammble



Causes serious eye irritation



Causes eye irritation



May cause drowsiness or dizziness



Keep container tightly closed in well-



May cause damage to organs

ventilated place



Keep container tightly closed in wellventilated place

Hydrochloric Acid 

Corrosive to metals



Skin corrosion



Eye damage



May cause respiratory irritation



Keep container tightly closed in well-



May cause respiratory irritation

ventilated place



Keep container tightly closed in well-

Sodium Hydroxide May be corrosive to metals 

Causes severe skin burns and eye damage

ventilated place

Petroleum Ether 

Extremely Flammable



Skin irritation



Causes serious eye irritation



Aspiration hazard



Keep container tightly closed in well-



Toxic to aquatic life



Keep container tightly closed in wellventilated place

Myristic Acid

ventilated place

Results Mass (g) 0.105 0.5

Trimyristin Mystric Acid Mixture of Trimyristin

Percentage yield 22.25% 185.04%

and Mystric Acid

% yield for Trimyristin

Percent yield ( % )=

experimental x 100 theoretical

Percent yield ( % )=

0.105( pure Trimyristin) x 100 0.472(crude Trimyristin)

0.105( pureTrimyristin) x 100=22.25 % 0.472(crude Trimyristin) Ratio of trimyristin to mystric acid is 1:3

0.105

g∗1 mol =0.000145196 mol of Trimyristin 723.16 g

0.256

g∗1mol =0.001120988 mol of Mystric acid 228.37 g

0.001120988 mol =0.000373663 mol 3 0.000373663∗723.16=0.27021 g

Theoretical :

Percent yield ( % )=

experimental x 100 theoretical

0.5 x 100=185.04 % 0.27021

Melting Point (oC) 58 60 55

The mixture of equal amounts of trimyristin and myristic acid had a melting point of 55oC, as shown in the table above. Discussion The melting point literature value for trimyristin is 56-58 oC and the value that was obtained was 58 oC. The value that was obtained fell around the range that was given. The literature melting point for mystric acid was 54-55 oC and the temperature that was obtained was 60 oC. That means that the melting point obtained for the trimyristin, was very accurate and the melting point for mystric acid was five degrees above the literature value. That indicates that the mystric acid that was isolated during the experiment was not pure. The percent yield for trimystrin was 22.25%. This could be that when performing the experiment to extract the pure trimyristin from the crude trimystin, some mass were lost in the. This is due to the vacuum filtration. When initially performing the experiment, some mass was sucked in because the filter paper wasn’t properly placed. The mystric acid portion was not obtained for my group due to human error. Therefore, the data collected by another group was used. The percent yield for mystric acid was with their data was 185.04%. This may be because of improper calculation and measurements that were done during the experiment. Since the boiling points both trimyristin and mystric acid are very similar. Then the melting point of a 50:50 ratio of the mixture was obtained. The melting point confirms that hydrolysis did occur and that the mixture of the two, reported to melt at 55 oC, are indeed mystric acid. Conclusion To an extent the results that were collected connect with the theoretical background. The first part of the experiment was close to the theoretical background the percent yield of the trimystrin extracted from the nutmeg was approximately about 36 %. The background provided that the weight of nutmeg is approximately 25-40% trimyristin. Therefore, the percent recovery falls within that range and supports

the information. However, for the second part of the experiment proper data was not obtained and another group’s data was used. The data that was collected revealed that overall this experiment was successful in extracting trimyristin from nutmeg and producing mystric acid through hydrolysis. Although the numbers were inaccurate, the process and idea of the experiment correlates with the procedure. Natural product chemistry can be applied to abundant of places. For example, it is used all the time for finding new medicine. Certain chemicals are extracted from plants for developments of new medication. The experiment did accomplish what it set out to do, The process through the experiment was educational and correlates with the background .

References Answers Ltd. Natural product chemistry. https://www.ukessays.com/essays/chemistry/naturalproduct-chemistry.php (accessed Feb 27, 2019).

Libretexts. 18.3: Reactions of Ethers - Acidic Cleavage. https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Map:_Organic_Chemistry_(Mc Murry)/Chapter_18:_Ethers_and_Epoxides;_Thiols_and_Sulfides/18.03_Reactions_of_Ethers :_Acidic_Cleavage (accessed Feb 27, 2019). Weldegirma, Solomon. “Experiment 6: Isolation of Trimyristin from Nutmeg and Preparation of Myristic Acid from Trimyristin by Hydrolysis.” Experimental Organic Chemistry. 8th Edition, Tampa, Pro-Copy Inc. 2018. 33-40....