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Organic Chemistry (8th Edition)
8th Edition
ISBN: 9780134042282
Author: Paula Yurkanis Bruice
Publisher: PEARSON
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Textbook Question
Chapter 21.3, Problem 9P
- a. Why is the pKa of the glutamate side chain greater than the pKa, of the aspartate side chain?
- b. Why is the pKa of the arginine side chain greater than the pKa of the lysine side chain?
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Students have asked these similar questions
Complete the following table. The only density needed is already given. Show your
calculations in a neat and easy-to-follow manner in the space below the table. All units
should be included and significant figures should be given close attention. Be sure to notice
that the amount of material should be in millimoles rather than moles, and the theoretical
mass of the product should in milligrams rather than grams.
LOCH 3
+
H2SO4
HNO 3
O=C-OCH 3
NO2
x
H₂O
F.W.
4.0 mL 1.3 M
amount
0.50 mL
in H2SO4
mg Theoretical
Theoretical
mmoles
density
1.09
Kumada Coupling:
1. m-Diisobutylbenzene below could hypothetically be synthesized by Friedel-Crafts reaction. Write out the reaction with a
mechanism and give two reasons why you would NOT get the desired product.
Draw the reaction (NOT a mechanism) for a Kumada coupling to produce the molecule above from m-dichlorobenzene.
Calculate the theoretical yield for the reaction in question 2 using 1.5 g of p-dichlorobenzene and 3.0 mL isobutyl bromide.
What signals appeared/disappeared/shifted that indicate that you have your intended product and not starting material? What
other impurities are present in your product and how do you know?
Wintergreen from Aspirin:
1. In isolating the salicylic acid, why is it important to press out as much of the water as possible?
2. Write the mechanism of the esterification reaction you did.
3.
What characteristic absorption band changes would you expect in the IR spectrum on going from aspirin to salicyclic acid and
then to methyl salicylate as you did in the experiment today? Give approximate wavenumbers associated with each functional
group change.
What signals appeared/disappeared/shifted that indicate that you have your intended product and not starting material? What
other impurities are present in your product and how do you know?
Chapter 21 Solutions
Organic Chemistry (8th Edition)
Ch. 21.1 - a. Explain why, when the imidazole ring of...Ch. 21.2 - a. Which isomer(R)-alanine or (S)-alanineis...Ch. 21.2 - Prob. 4PCh. 21.3 - Prob. 5PCh. 21.3 - Prob. 6PCh. 21.3 - Draw the predominant form for glutamate in a...Ch. 21.3 - a. Why is the pKa of the glutamate side chain...Ch. 21.4 - Calculate the pI of each of the following amino...Ch. 21.4 - a. Which amino acid has the lowest pI value? b....Ch. 21.4 - Prob. 12P
Ch. 21.4 - Prob. 13PCh. 21.4 - Explain why the pI of lysine is the average of the...Ch. 21.5 - What aldehyde is formed when valine is treated...Ch. 21.5 - Prob. 16PCh. 21.5 - Prob. 17PCh. 21.5 - Prob. 18PCh. 21.5 - Prob. 19PCh. 21.6 - Why is excess ammonia used in the preceding...Ch. 21.6 - Prob. 21PCh. 21.6 - What amino acid is formed using the...Ch. 21.6 - Prob. 23PCh. 21.6 - What amino acid is formed when the aldehyde used...Ch. 21.7 - Esterase is an enzyme that catalyzes the...Ch. 21.8 - Draw the tetrapeptide Ala-Thr-Asp-Asn and indicate...Ch. 21.8 - Draw the resonance contributors of the peptide...Ch. 21.8 - Which bonds in the backbone of a peptide can...Ch. 21.9 - An opioid pentapeptide has the following...Ch. 21.9 - What is the configuration about each of the...Ch. 21.9 - Glutathione is a tripeptide whose function is to...Ch. 21.10 - What dipeptides would be formed by heating a...Ch. 21.10 - Suppose you are trying to synthesize the dipeptide...Ch. 21.10 - Show the steps in the synthesis of the...Ch. 21.10 - a. Calculate the overall yield of bradykinin when...Ch. 21.11 - Show the steps in the synthesis of the...Ch. 21.13 - Prob. 37PCh. 21.13 - In determining the primary structure of insulin,...Ch. 21.13 - A decapeptide undergoes partial hydrolysis to give...Ch. 21.13 - Explain why cyanogen bromide does not cleave on...Ch. 21.13 - Indicate the peptides produced from cleavage by...Ch. 21.14 - Prob. 43PCh. 21.14 - Three peptides were obtained from a trypsin...Ch. 21.14 - Prob. 45PCh. 21.15 - How would a protein that resides in the nonpolar...Ch. 21.16 - a. Which would have the greatest percentage of...Ch. 21.17 - When apples that have been cut are exposed to...Ch. 21 - Glycine has pK2 values of 2.34 and 9.60. At what...Ch. 21 - Prob. 50PCh. 21 - A titration curve is a plot of the pH of a...Ch. 21 - Prob. 52PCh. 21 - Aspartame (its structure is on page 1007) has a pl...Ch. 21 - Draw the form of aspartate that predominates at...Ch. 21 - Show how phenylalanine can be prepared by...Ch. 21 - A professor was preparing a manuscript for...Ch. 21 - What aldehydes are formed when the following amino...Ch. 21 - Prob. 58PCh. 21 - Determine the amino acid sequence of a polypeptide...Ch. 21 - Prob. 60PCh. 21 - Prob. 61PCh. 21 - Which is the more effective buffer at...Ch. 21 - Identify the location and type of charge on the...Ch. 21 - Draw the product obtained when a lysine side chain...Ch. 21 - After the polypeptide shown below was treated with...Ch. 21 - Treatment of a polypeptide with 2-mercaptoethanol...Ch. 21 - Show how aspartame can be synthesized using DCCD.Ch. 21 - -Amino acids can be prepared by treating an...Ch. 21 - Reaction of a polypeptide with carboxypeptidase A...Ch. 21 - a. How many different octapeptides can be made...Ch. 21 - Glycine has pKa values of 2.3 and 9.6. Do you...Ch. 21 - A mixture of 15 amino acids gave the fingerprint...Ch. 21 - Write the mechanism for the reaction of an amino...Ch. 21 - Prob. 74PCh. 21 - Show how valine can be prepared by a. a...Ch. 21 - The primary structure of -endorphin, a peptide...Ch. 21 - A chemist wanted to test his hypothesis that the...Ch. 21 - Propose a mechanism for the rearrangement of the...Ch. 21 - A normal polypeptide and a mutant of the...Ch. 21 - Determine the amino acid sequence of a polypeptide...
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- Synthesis of ZybanⓇ: 1. Write a mechanism for the bromination of m-chloropropiophenone. Br₂ CH2Cl2 Cl Br 2. Give the expected m/z (to a round number) for the molecular ion from the product above (including isotopic peaks). 3. What signals appeared/disappeared/shifted that indicate that you have your intended product and not starting material? What other impurities are present in your product and how do you know?arrow_forwardSynthesis of Ibuprofen-Part 2: 1. Some pain relievers including ibuprofen (MotrinⓇ) and naproxen (Aleve®) are "α-arylpropanoic acids." Look up the structure of naproxen (AleveⓇ), another a-arylpropionic acid. Using the same reactions that we used for making ibuprofen, show how to make naproxen from the compound below. Show all intermediates and reagents in your synthesis. Show how you would prepare ibuprofen starting from p-isobutylbenzene rather than p-isobutylacetophenenone. What reaction steps would need to change/add? 3. What signals appeared/disappeared/shifted that indicate that you have your intended product and not starting material? What other impurities are present in your product and how do you know?arrow_forwardAcid Catalyzed Aromatization of Carvone: 1. Starting with the ketone, below, draw a mechanism for the reaction to give the phenol as shown. H2SO4 HO- H₂O 2. Why do we use CDCl instead of CHCl, for acquiring our NMR spectra? 3. Why does it not matter which enantiomer of carvone is used for this reaction? What signals appeared/disappeared/shifted that indicate that you have your intended product and not starting material? What other impurities are present in your product and how do you know?arrow_forward
- Assign this H NMRarrow_forwardPlease complete these blanks need that asaparrow_forwardNitration of Methyl Benzoate: 1. Predict the major product for the reaction below AND provide a mechanism. Include ALL resonance structures for the intermediate. C(CH3)3 NO₂* ? 2. Assuming the stoichiometry is 1:1 for the reaction above, what volume of concentrated nitric acid would be required to mononitrate 0.50 grams of the compound above? What product(s) might you expect if you nitrated phenol instead of methyl benzoate? Explain your reasoning. What signals appeared/disappeared/shifted that indicate that you have your intended product and not starting material? What other impurities are present in your product and how do you know?arrow_forward
- Sodium Borohydride Reduction (continued on the next page): 1. Draw the product of each of the reactions below and give the formula mass to the nearest whole number. ? (1) NaBH (2) acid (1) NaBD4 (2) acid ? 2. In mass spectra, alcohols typically break as shown in equation 8 in chapter 11 (refer to your lab manual). The larger group is generally lost and this gives rise to the base peak in the mass spectrum. For the products of each of the reactions in question # 1, draw the ion corresponding to the base peak for that product and give its mass to charge ratio (m/z). 3. Given the reaction below, calculate how many mg of 1-phenyl-1-butanol that can be produced using 31 mg NaBH4 and an excess of butyrophenone. 4. + NaBH4 OH (after workup with dilute HCI) What signals appeared/disappeared/shifted that indicate that you have your intended product and not starting material? What other impurities are present in your product and how do you know?arrow_forwardAspirin from Wintergreen: 1. In isolating the salicylic acid, why is it important to press out as much of the water as possible? Write a step-by-step mechanism for the esterification of salicylic acid with acetic anhydride catalyzed by concentrated H₂SO4. 3. Calculate the exact monoisotopic mass of aspirin showing your work. What signals appeared/disappeared/shifted that indicate that you have your intended product and not starting material? What other impurities are present in your product and how do you know?arrow_forwardSynthesis of Ibuprofen-Part 1: 1. What characteristic absorption band changes would you expect in the IR spectrum on going from p-isobutylacetophenone to 1-(4-isobutylphenyl)-ethanol and then to 1-(4-isobutylphenyl)-1-choroethane as you did in the experiment today? Give approximate wavenumbers associated with each functional group change. Given that the mechanism of the chlorination reaction today involves formation of a benzylic carbocation, explain why the following rearranged product is not formed. محرم محمد 3. Why do we use dilute HCl for the first step of the reaction today and concentrated HCI for the second step? What signals appeared/disappeared/shifted that indicate that you have your intended product and not starting material? What other impurities are present in your product and how do you know?arrow_forward
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