Experiment 5 - carvone epoxidation
pdf
School
University of Oregon *
*We aren’t endorsed by this school
Course
348
Subject
Chemistry
Date
Feb 20, 2024
Type
Pages
5
Uploaded by ElderTigerPerson699
CH 348 Winter 2024 1 Experiment 5. Epoxidations of Carvone In this lab we will oxidize carvone, using two different oxidizing agents, and will determine the regioselectivity of both reactions. Both reactions are known to convert alkenes to epoxides. You will be given the 1
H NMR spectrum of carvone (posted on Canvas) and will need to run both reactions and determine the relative amounts of the three possible epoxidation products shown below by 1
H NMR spectroscopy. The oxidizing reagents we will be using in this lab are m-chloroperoxybenzoic acid (mCPBA), and hydrogen peroxide in base. The mCPBA oxidation will be set up in one lab period and worked up in the second lab period. The reaction requires > 4 hrs at room temperature to go to completion. The hydrogen peroxide oxidation will be set up and worked up in the first lab period; this reaction only requires ~30 minutes. For both reactions we will isolate the crude product using an aqueous work up and submit the crude product for 1
H NMR analysis to determine the regioselectivity. Pre-Lab Follow the Lab Notebook Guidelines. Include a reagent table for both reactions. Procedure Hydrogen peroxide oxidation:
To a scintillation vial, add carvone (500 mg) and methanol (6 mL). Add a small stir bar
Cool in an ice-bath. Stir.
Add an aqueous solution of hydrogen peroxide (30%, 1.2 mL)
Add 6M NaOH (0.7 mL) dropwise.
After 15 minutes let the reaction warm to room temperature.
Stir for 30 minutes.
Transfer the reaction mixture to a separatory funnel and add ~20 mL of ether.
Wash with water (2 x 15 mL)
Wash with brine (15 mL)
CH 348 Winter 2024 2
Dry (Na
2
SO
4
), filter and rotovap to obtain the crude product.
Submit a sample for 1
H NMR spectroscopy.
TLC your crude product vs carvone (10% EtOAc / hex; UV / I
2
stain). You will need to make a dilute solution of your crude product (1 ~ 10 mg / mL) for spotting on the TLC plate. You can use any volatile solvent that the product is soluble in (CH
2
Cl
2
, acetone, ether…). mCPBA oxidation:
To a scintillation vial, add carvone (500 mg) and CH
2
Cl
2
(12 mL). Add a small stir bar.
Cool in an ice-bath. Stir.
Slowly add mCPBA* (842 mg). Most of the reagent should dissolve. Make sure that the stir bar continues to stir the reaction mixture throughout the addition.
After a few minutes let the reaction warm to room temperature. Continue stirring until near the end of the lab period.
Near the end of the lab period, cap and label the vial, and keep in your lab drawer until next lab period.
Vacuum filter the reaction mixture, washing with a minimal amount of CH
2
Cl
2
(2 x 1 mL). The solid is m-chlorobenzoic acid, which is waste.
Transfer the filtrate to a separatory funnel and add ~30 mL of ether.
Wash with 5 x 15 mL 0.6 M NaHCO
3
(if the organic layer ends up on the bottom of the sep funnel, add more ether). Be very careful here.
Sodium bicarbonate and acid produces carbon dioxide which can cause the pressure in the separatory funnel to build up. Vent frequently!!!
Wash with brine (15 mL).
Dry (Na
2
SO
4
), filter and rotovap to obtain the crude product.
Submit a sample for 1
H NMR spectroscopy.
TLC your crude product vs carvone (10% EtOAc / hex; UV / I
2
stain). You will need to make a dilute solution of your crude product (1 ~ 10 mg / mL) for spotting on the TLC plate. You can use any volatile solvent that the product is soluble in (CH
2
Cl
2
, acetone, ether…). *mCPBA is ~75% pure; the remainder is m-chlorobenzoic acid Waste disposal:
All aqueous solutions can go into the aqueous waste containers. All solutions where an organic solvent is the main component must go into the organic waste container.
CH 348 Winter 2024 3 Submitting Samples for NMR Spectroscopy
Normally you would need to check for solubility in CHCl
3
. If soluble, you would use CDCl
3
to prepare the NMR sample. If it’s not solube, then you would test the protonated version of other common NMR solvents until you find one that works (other commonly used NMR solvents: d6-DMSO, d6-acetone, D
2
O). You do not need to do that for this lab, we will be using CDCl
3
.
Place ~ 15 mg of the product in a clean scintillation vial (do not submit the sample you used to check solubility!!). If you need to transfer the material in solution, be sure to evaporate the solvent before submitting the sample.
Fill in the next available line on the NMR sign up sheet and properly label samples!!**
Record the Compound ID from the sign up sheet in your notebook.
NMR data (FID) will be posted on Canvas using the filename (Compound ID) on the sign up sheet.
Download the file and rename it according to your notebook reference.
Process the data using Mestrenova. ** You will fill out the NMR labels in duplicate – one label affixed around the vial; the other to the cap (there is a sample vial in the lab). The Compound ID is listed on the sign up sheet.
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
- Access to all documents
- Unlimited textbook solutions
- 24/7 expert homework help
CH 348 Winter 2024 4 Post-Lab Report 1. For the reaction with mCPBA: Why is the reaction washed multiple times with aqueous sodium bicarbonate? [5 points] 2. For both aqueous workups, the reaction mixture was diluted with diethyl ether then washed with various aqueous solutions. Why was the mixture diluted with diethyl ether instead of dichloromethane (the workup does work equally well if you use dichloromethane instead of diethyl ether)? What would be different if we used dichloromethane instead of diethyl ether? [5 points] 3. Explain how TLC can be used to follow the progress of a reaction. How many products are indicated for each reaction by TLC? Does your TLC for each reaction show any evidence of starting material? [10 points] 4. Determine the regioselectivity of both reactions. Clearly show how you arrived at your answer. Include appropriate figures to aid your explanation. You will be graded not only on your answer, but also on how clearly you present the data. [40 points] 5. Write complete curved arrow mechanisms for both reactions. [20 points] 6. Provide a cogent explanation for the observed regioselectivities. [20 points] --------------------- [100 points]
CH 348 Winter 2024 5 Carvone:
1
H NMR (300 MHz, CDCl
3
)
Related Documents
Related Questions
In the UV–vis spectrum of benzene, the absorption that corresponds to the HOMO–LUMO transition occurs at 184 nm.How does this compare to the corresponding electron transition in hexa-1,3,5-triene (see Table 15-1)? Explain why there is a significant difference.
arrow_forward
When 1-bromobutane is treated with sodium acetate (CH3CO,Na), the major product for the
reaction is an ester (CH;CO2CH2CH2CH2CH3). Explain how mass spectrometry and IR spectroscopy
could be used to prove that the reaction has occurred and you no longer have the starting material.
arrow_forward
Please help me assign the protons for the H^1 NMR for p-nitrobenzaldehyde as seen in the photo! You can ignore the “water” and “dichloromethane” labels.
arrow_forward
Compare the 13C NMR spectra of isoborneol and camphor. Explain which peaks can be used to determine whether the oxidation was successful.
Propose a mechanism for this oxidation. To simplify the structures, use benzyl alcohol to draw the mechanism instead of isoborneol. Include the formation of any byproduct(s) in the mechanism.
arrow_forward
Hydrohalic acids (i.e., HCl, HBr, HI) add to the double bond of alkenes to yield alkyl halides. Shown below is the carbon NMR spectrum of an alkene of formula C5H10. What is the structure of this alkene?
arrow_forward
The ultraviolet absorption spectrum of 4-methyl-3-pent-2-one in ethanol is
shown below. Determine Amax and ɛ for this compound. The concentration of
the solution used was 6.20 × 10-5 moles•L-¹, and the cell path was 1.00 cm.
Absorbance
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
200
nm
250
300
CH3 H
1
C=C
400
1
CH3 C-CH3
11
500
arrow_forward
2
The IR and 1H-NMR spectra of a compound with molecular formula C4H7ClO2 are shown below. Your objective as a group is to propose a structure for this compound, explaining how you reach your decision. Using all the information you have been given, in a post with others in your group share your initial ideas about the possible structure of the compound. Then use comments to interact with the other students in the group and propose a final answer to the problem. In the comment phase, you should comment on the postings of at least two other students.
arrow_forward
Use the spectrometric data below to elucidate a structure. They will be a combination of 1H NMR, 13C NMR, IR, and MS.
arrow_forward
The oxidation of 3-pentanol to 3-pentanone was performed in the lab and an IR was taken of the finished product.
(a) what are the key functional groups in the starting material, 3-pentaol?
(b) what are the key functional groups in the product, 3-pentanone?
(c) based on the IR spectrum below, was the experiment successful, and, if so, how pure was the product? Explain your reasoning.
arrow_forward
Most of the pKa values given in this text were determined in water. How would the pKa values of carboxylic acids, alcohols, ammonium ions (RN+H3) , phenol, and an anilinium ion (C6H5N+H3) + change if they were determined in a solvent less polar than water
arrow_forward
14. predict the product of the raction below. Which of the following change(s) in the IR spectrum is consistent with conversion of the reactant to product
arrow_forward
Annotate the Mass Spec, 1H NMR, and 13C NMR for C4H11N or Butylamine
Annotate the Mass Spec, 1H NMR, and 13C NMR for C4H8O or Butraldehyde
Annotate the Mass Spec, 1H NMR, and 13C NMR for C5H8O or Cyclopentanone
Thanks :)
arrow_forward
please fill out the chart or part of it based on the compound
arrow_forward
When 2-chlorohexane is treated with sodium ethoxide (NaOCH2CH3), the major product for the reaction is
2-hexene. Explain how mass spectrometry and IR spectroscopy could be used to prove that the reaction has
occurred and you no longer have 2-chlorohexane.
28.
arrow_forward
How many peaks would each compound show in their 13C NMR spectrum?
a) eucalyptol
b) linalool
arrow_forward
Draw the structure of the product in your notebook. Using the provided spectra, assign each set of hydrogen atoms and carbon atoms in the product to the signals in the 1H NMR and 13C NMR spectra. Analyze the IR spectra for 2-methyl-2-propanol and 2-chloro-2-methylpropane. Identify the bands in each spectra that are needed to confirm the disappearance of the alcohol band and appearance of the new C-Cl band.?
Please don't provide hand written solution......
arrow_forward
Use the spectrometric data below to elucidate a structure. They will be a combination of 1H NMR, 13C NMR, IR, and MS.
arrow_forward
a.) Alkene
b.) Alkyne
c.) Carboxylic acid
d.) ester
e.) ether
arrow_forward
How would you use IR and ¹H-NMR spectroscopy to distinguish between these two isomeric compounds?
For IR, consider the absorption of the carbonyl group.
For ¹H-NMR, consider the number of signals observed.
Select the IR frequency and number of NMR signals that is diagnostic for either isomer a or isomer b.
Isomer A: cyclopentanecarboxamide
Isomer B: 6-hydroxyhexanenitrile
IR:
¹H-NMR:
cm-1.
a-4
a-5
b-3
b-4
b-5
b-6
signals
a-1680
a-1690
a-1735
a-1810
a-2250
b-1650
b-1690
b-1710
b-2250
24
arrow_forward
What is the reactant and the desired product? If you were looking at both of the IR spectrum, where would you confirm that the desired reaction had occured.
arrow_forward
Please answer this question pertianing to organic chemistry.
arrow_forward
3. (Chapter 13 - Q58c) The compound whose H NMR spectrum is shown has the
molecular formula C3H9B1. Follow the following questions to predict the unknown
structure.
Chem. Rel.
shift area
3.16
1.00
3.56
1.00
1.00
1.50
Z18
729
TMS
10
O ppm
Chemical shift (8)
ng
3(a) Degree of the unsaturation of this compound =
3(b) The two peaks at 3.16 8 and 3.56 ő indicate two triplets Yes or NO =
3(c) The compound has 2 CH2 groups Yes or No =
3(d) Depending on the two triplets' chemical shifts one of the CH2 may have attached to
the Br, Yes or No =
3(e) The multiplet at 7.18 õ to 7.29 õ indicate that compound is. disubstituted
benzene -
3(f) The name of the unknown compound is =
Intensity
arrow_forward
Interpret the NMR spectra and identify these compounds:
choices:
4-Chloroacetanilide
Diphenylmethanol
Ethyl 4-hydroxybenzoate
Phenacetin
2-Chloroacetanilide
include integration number and multiplicity
arrow_forward
Nitesh
arrow_forward
What factors during the experiment caused the percent yield to be different than 100%? What impurities may be present in the final product (look at the spectroscopic data for evidence of this), and how does that effect the percent yield calculation?
I got 64% for the percent yield.
arrow_forward
SEE MORE QUESTIONS
Recommended textbooks for you

Chemistry
Chemistry
ISBN:9781305957404
Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:Cengage Learning

Chemistry
Chemistry
ISBN:9781259911156
Author:Raymond Chang Dr., Jason Overby Professor
Publisher:McGraw-Hill Education

Principles of Instrumental Analysis
Chemistry
ISBN:9781305577213
Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher:Cengage Learning

Organic Chemistry
Chemistry
ISBN:9780078021558
Author:Janice Gorzynski Smith Dr.
Publisher:McGraw-Hill Education

Chemistry: Principles and Reactions
Chemistry
ISBN:9781305079373
Author:William L. Masterton, Cecile N. Hurley
Publisher:Cengage Learning

Elementary Principles of Chemical Processes, Bind...
Chemistry
ISBN:9781118431221
Author:Richard M. Felder, Ronald W. Rousseau, Lisa G. Bullard
Publisher:WILEY
Related Questions
- In the UV–vis spectrum of benzene, the absorption that corresponds to the HOMO–LUMO transition occurs at 184 nm.How does this compare to the corresponding electron transition in hexa-1,3,5-triene (see Table 15-1)? Explain why there is a significant difference.arrow_forwardWhen 1-bromobutane is treated with sodium acetate (CH3CO,Na), the major product for the reaction is an ester (CH;CO2CH2CH2CH2CH3). Explain how mass spectrometry and IR spectroscopy could be used to prove that the reaction has occurred and you no longer have the starting material.arrow_forwardPlease help me assign the protons for the H^1 NMR for p-nitrobenzaldehyde as seen in the photo! You can ignore the “water” and “dichloromethane” labels.arrow_forward
- Compare the 13C NMR spectra of isoborneol and camphor. Explain which peaks can be used to determine whether the oxidation was successful. Propose a mechanism for this oxidation. To simplify the structures, use benzyl alcohol to draw the mechanism instead of isoborneol. Include the formation of any byproduct(s) in the mechanism.arrow_forwardHydrohalic acids (i.e., HCl, HBr, HI) add to the double bond of alkenes to yield alkyl halides. Shown below is the carbon NMR spectrum of an alkene of formula C5H10. What is the structure of this alkene?arrow_forwardThe ultraviolet absorption spectrum of 4-methyl-3-pent-2-one in ethanol is shown below. Determine Amax and ɛ for this compound. The concentration of the solution used was 6.20 × 10-5 moles•L-¹, and the cell path was 1.00 cm. Absorbance 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 200 nm 250 300 CH3 H 1 C=C 400 1 CH3 C-CH3 11 500arrow_forward
- 2 The IR and 1H-NMR spectra of a compound with molecular formula C4H7ClO2 are shown below. Your objective as a group is to propose a structure for this compound, explaining how you reach your decision. Using all the information you have been given, in a post with others in your group share your initial ideas about the possible structure of the compound. Then use comments to interact with the other students in the group and propose a final answer to the problem. In the comment phase, you should comment on the postings of at least two other students.arrow_forwardUse the spectrometric data below to elucidate a structure. They will be a combination of 1H NMR, 13C NMR, IR, and MS.arrow_forwardThe oxidation of 3-pentanol to 3-pentanone was performed in the lab and an IR was taken of the finished product. (a) what are the key functional groups in the starting material, 3-pentaol? (b) what are the key functional groups in the product, 3-pentanone? (c) based on the IR spectrum below, was the experiment successful, and, if so, how pure was the product? Explain your reasoning.arrow_forward
- Most of the pKa values given in this text were determined in water. How would the pKa values of carboxylic acids, alcohols, ammonium ions (RN+H3) , phenol, and an anilinium ion (C6H5N+H3) + change if they were determined in a solvent less polar than waterarrow_forward14. predict the product of the raction below. Which of the following change(s) in the IR spectrum is consistent with conversion of the reactant to productarrow_forwardAnnotate the Mass Spec, 1H NMR, and 13C NMR for C4H11N or Butylamine Annotate the Mass Spec, 1H NMR, and 13C NMR for C4H8O or Butraldehyde Annotate the Mass Spec, 1H NMR, and 13C NMR for C5H8O or Cyclopentanone Thanks :)arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- ChemistryChemistryISBN:9781305957404Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCostePublisher:Cengage LearningChemistryChemistryISBN:9781259911156Author:Raymond Chang Dr., Jason Overby ProfessorPublisher:McGraw-Hill EducationPrinciples of Instrumental AnalysisChemistryISBN:9781305577213Author:Douglas A. Skoog, F. James Holler, Stanley R. CrouchPublisher:Cengage Learning
- Organic ChemistryChemistryISBN:9780078021558Author:Janice Gorzynski Smith Dr.Publisher:McGraw-Hill EducationChemistry: Principles and ReactionsChemistryISBN:9781305079373Author:William L. Masterton, Cecile N. HurleyPublisher:Cengage LearningElementary Principles of Chemical Processes, Bind...ChemistryISBN:9781118431221Author:Richard M. Felder, Ronald W. Rousseau, Lisa G. BullardPublisher:WILEY

Chemistry
Chemistry
ISBN:9781305957404
Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:Cengage Learning

Chemistry
Chemistry
ISBN:9781259911156
Author:Raymond Chang Dr., Jason Overby Professor
Publisher:McGraw-Hill Education

Principles of Instrumental Analysis
Chemistry
ISBN:9781305577213
Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher:Cengage Learning

Organic Chemistry
Chemistry
ISBN:9780078021558
Author:Janice Gorzynski Smith Dr.
Publisher:McGraw-Hill Education

Chemistry: Principles and Reactions
Chemistry
ISBN:9781305079373
Author:William L. Masterton, Cecile N. Hurley
Publisher:Cengage Learning

Elementary Principles of Chemical Processes, Bind...
Chemistry
ISBN:9781118431221
Author:Richard M. Felder, Ronald W. Rousseau, Lisa G. Bullard
Publisher:WILEY