in lab we put methyl oleate in a reaction flask with Pd/c and methanol. we put the mixture in a water bath with a bubble trap and bubble producer (Zn and H2SO4). I am trying to calculate the percent yield. I just want to make sure that the mass of the reactant (methyl oleate) should equal the mass of the product (methyl stearate) because I just changed the bonds in the molecule, I didn't add any substituents to it. Is this correct?

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Looking for a catalytic hydogenation mechanism of the starting material methyl oleate to the product methyl stearate. A detailed electron pushing mechanism with arrows and the mechanistic steps under each arrow. Please !

CHM 2260 Winter 2018 ORGANIC CHEMISTRY LABORATORY II Reaction Preparation # 7 OBJECTIVE Catalytic Hydrogenation To generate methyl stearate from methyl oleate using a transition metal catalyst with hydroge and rate the efficiency of that synthesis using TLC, melting point, FT-IR, mass, spectra. mass, 'H- and C-NMR REACTIONS Hz, Pd-C 0 PROCEDURE 1. Assemble the hydrogen delivery apparatus as instructed. Get your apparatus approved before continuing. 2. Use a 1 ml syringe to add 1.5 mmol of methyl oleate to the 25 mL round bottom flask already holding a small stir bar, followed by 10 mL of methanol. Weigh out 0.015-0.025 g of palladium on carbon catalyst and add it to the flask using a dry glass funnel. Using a dry funnel helps getting as much of the catalyst as possible into the solution. Then flush residual catalyst into the flask using 5 ml of methanol. CAUTION: Addition of the catalyst occasionally causes a flash. Have a watch glass ready to cover the flask opening should this occur 3. When these steps have been completed, begin flushing your reaction flask with nitrogen.Once the nitrogen balloon is empty, replace it with a hydrogen balloon. Use a 100 mL beaker full of warm water to warm the heterogeneous reaction mixture. You may need to change the water or H2 balloon during the reaction. Continue for 1 h. WORKUP 4. After the hydrogen gas has been consumed, exchange the hydrogen balloon with one filled with nitrogen and flush your apparatus with nitrogen. Add 10 mL of diethyl ether to the reaction mixture to help dissolve the product, which might solidify once heating is stopped. 5. Using a fluted funnel and filter paper, carefully filter the reaction mixture into a clean, dry, tared 50 mL round bottom flask. Using a capillary, take a sample for TLC, then rotovap the product to dryness. 6. Assuming an excess of hydrogen, calculate percent yield of the product. 7. Perform appropriate TLC and melting point analysis on your product. Obtain FT-IR, mass, 'H NMR- and C NMR-spectra for the pure product from your instructor. Assign all peaks to structural moieties in the product. Report this information on your Analytical Data Sheet

Miniscale nitration of methyl benzoate was performed in the lab:

Procedure below:

1. Prepare and ice bath in a 100mL beaker on a magnetic stir plate.

2. To a clean, dry 25 mL Erlenmeyer flask, add 1.0 mL of methyl benzoate via pipet.

3. Calculate the mass of methyl benzoate.

4. To the methyl benzoate, add 2.25 mL of concentrated (18M) sulfuric acid and a spin bar.

5. Carefully clamp the flask so that it is immersed in the ice bath and begin stirring.

6. Prepare the nitrating solution by adding 0.75mL of concentrated (18M) sulfuric acid and 0.75mL of concentrated (16M) nitric acid to a clean, dry vial.

7. Cool the mixture in a second ice bath.

8. With a Pasteur pipet, slowly add the cooled sulfuric acid-nitric acid solution to the stirred solution of methyl benzoate. *Addition should take approximately 15 minutes. Adding the nitrating agent more rapidly will increase the amount of by-products and decrease the yield

9. After all of the nitrating agent has been added, carefully remove the ice bath.

10. Continue stirring until the reaction has come to room temperature.

11. Then let the reaction flask stand undisturbed for 15 minutes.

12. Place 10 g of ice in a 100mL beaker.

13. With a Pasteur pipet, carefully transfer the reaction mixture to the beaker.

14. Rinse the flask with 5mL of cold water.

15. When the ice has melted, vacuum filter the crude crystals using a Buchner funnel.

16. Wash the crystals with 2 5mL portions of cold water and finally with 2 1.5mL of cold methanol.

17. The crude product can be recrystallized from methanol.

18. Record the mass of the dry product and calculate the yield.

QUESTION: What is the major product formed in this reaction? Justify your reasoning..

Hello I need help with calculating the theoretical yields. All the information are given below. The images of the equations couldn't be uploaded.

Nitration of Methyl benzoate, acetanilide and Competition

Experimental Procedure:

Nitration of Methyl Benzoate

A. Preparation of the Nitrating Agent

1. Support a small test tube in an Erlenmeyer flask.

2. Using the small plastic dropping bottles, add 20 drops of concentrated acetic acid, 40 drops of

concentrated sulfuric acid, and 16 drops of concentrated nitric acid.

3. Swirl the mixture and set aside to be used later.

B. Nitration of Methyl Benzoate

4. Place a magnetic stir bar in a 25 mL Erlenmeyer flask and add 0.2 g of methyl benzoate.

Methyl benzoate is a liquid so place the Erlenmeyer flask on the balance, zero the balance, and add drop wise until the mass is 0.2 g (record exact mass used if slightly different than 0.2 g).

5. Add 20 drops of concentrated acetic acid and 40 drops of concentrated sulfuric acid.

Place the flask in an ice bath (small beaker with some ice and a little water) and stir for several minutes to dissolve the methyl benzoate (a homogeneous solution is achieved).

While stirring, use a glass pipette to add the solution of the nitrating agent drop wise over 3 minutes.

Remove the reaction from the ice bath and stir for an additional 20 minutes.

After 20 minutes, add a few pieces of crushed ice directly to the reaction mixture.

After the ice has melted, slowly 5 mL of saturated sodium bicarbonate.

Collect the product using vacuum filtration and wash the final product with a 5 mL of cold water and allow it to dry under vacuum for several minutes.

Record the mass of the final product, measure the melting point, calculate the percent yield and obtain an IR spectrum.

Nitration of Methyl benzoate, acetanilide and Competition

Nitration of Acetanilide

A. Preparation of the Nitrating Agent

1. Support a small test tube in an Erlenmeyer flask.

2. Using the small plastic dropping bottles, add 20 drops of concentrated acetic acid, 40 drops of concentrated sulfuric acid, and 16 drops of concentrated nitric acid.

3. Swirl the mixture and set aside to be used later.

B. Nitration of Acetanilide

4. Place a magnetic stir bar in a 25 mL Erlenmeyer flask and add 0.2 g of acetanilide.

5. Add 20 drops of concentrated acetic acid and 40 drops of concentrated sulfuric acid.

6. Place the flask in an ice bath (small beaker with some ice and a little water) and stir for several minutes to dissolve the acetanilide.

7. While stirring, use a glass pipette to add the solution of the nitrating agent drop wise over 3 minutes.

Remove the reaction from the ice bath and stir for an additional 20 minutes.

After 20 minutes, add a few pieces of crushed ice directly to the reaction mixture.

After the ice has melted, slowly 5 mL of saturated sodium bicarbonate.

Collect the product using vacuum filtration and wash the final product with a 5 mL of cold water and allow it to dry under vacuum for several minutes.

Record the mass of the final product, measure the melting point, calculate the percent yield and obtain an IR spectrum.

Nitration of Methyl benzoate, acetanilide and Competition

Competition Experiment (Methyl Benzoate vs. Aectanilide)

A. Preparation of the nitrating agent

Support a small test tube in an Erlenmeyer flask.

Using the small plastic dropping bottles, add 2 drops of concentrated nitric acid, 10 drops of concentrated acetic acid, and 20 drops of concentrated sulfuric acid.

Gently swirl the mixture and set aside to be used later.

B. Competition Experiment

Set a 25 mL Erlenmeyer flask on the balance, zero the balance and add 0.1 g methyl benzoate (add this reagent first because it is a liquid).

Measure 0.1 g acetanilide (using weighing paper) and add this to the 25 mL Erlenmeyer flask containing the methyl benzoate.

Add 10 drops of concentrated acetic acid and 20 drops of concentrated sulfuric acid.

Place a magnetic stir bar in the flask and begin stirring.

Place the Erlenmeyer flask in an ice bath and add the solution of the nitrating agent drop wise over 5 minutes.

Remove the reaction from the ice bath and stir for an additional 10 minutes.

After 10 minutes, add a few pieces of crushed ice directly to the reaction mixture.

After the ice has melted, slowly 5 mL of saturated sodium bicarbonate.

Collect the product using vacuum filtration and wash the final product with a 5 mL of cold water and allow it to dry under vacuum for several minutes.

Record the mass of the final product, measure the melting point, calculate the percent

yield and obtain an IR spectrum.

Nitration of Methyl benzoate, acetanilide and Competition

Pre Lab Questions

1. Fill in the appropriate data in the tables below and calculate the theoretical yield. (Use

the amounts of materials that will be used from the experimental section above)

Molecular Weight
amount				Theoretical yield
moles
density/concentration (if applicable)
Equivalents

Molecular Weight
amount				Theoretical yield
moles
density/concentration (if applicable)
Equivalents

2. Look up the melting point of methyl-2-nitrobenzoate, methyl-3-nitrobenzoate, methyl-

4-nitrobenzoate, 2-nitroacetanilide, and 4-nitroacetanilide (and record the reference(s)

used)

3. Which product is expected from the nitration of methyl benzoate based on the directing

nature of the ester?

4. Based on the predicted reactivities of methyl benzoate compared to acetanilide, what

product is expected from the competition experiment.

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Theoretical Yield

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Equivalents