Microsoft Word - CS 3 Fa20 Masters.docx
CHEM 202 CS 3: Polar Acidic Reactions Dr. Masters
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Please upload this completed CS on Thursday, November
19 by 11:59 pm to Canvas. To do so, go to “Assignments” on
Canvas and click on the Case Study 3 assignment. Here, you
will be able to upload one pdf file.
This case study is worth 100 points. You are allowed to use
your class materials and your CHEM 202 textbook. You will
need to reference your class notes, ex: Unit 3 – topic name,
page ##.
You may work with another student. If so:
o Please fill out both students’ info in the table above.
o Each team member must upload one copy. Remember,
you can work together via Zoom since each of you have
your own Zoom meeting room. Use a Google Jamboard
or the Zoom Whiteboard to work out the problems
during your virtual meetings.
o If you worked with a partner on this first case study, you
are not obligated to work with that partner again in the
future. It’s your choice!
o You can only work with one other student from our
section (only Dr. Masters’ section of CHEM 202).
Only use the space provided for your answers! Do not add
pages, use the back of the page, etc. Write concisely and neatly!
Here are ways to complete and submit this assignment:
1. Print out this case study, hand-draw your answers,
scan it*, and upload as a pdf to Canvas.
2. If you do not have a printer, write your answers on
lank sheets of paper. Please set up the pages as you
see here: landscape orientation, two columns: “Main
Questions” and “Supporting Questions”. Scan and
upload as a pdf file to Canvas.
3. Use your tablet to complete it electronically using a
stylus. Upload the electronic pdf file to Canvas.
*You can use the apps Camscanner or Scannable for scanning
documents using your phone. If you have an iPhone, you can
use the “Notes” app to generate a pdf file. You must generate
one pdf file for submission. It is your responsibility to
make sure your submissions are complete and legible.
Missing/illegible parts to the assignment will receive no
credit and will not be accepted late.
Academic Integrity & Honor Code. By providing your
signature, you are agreeing to not using any outside help (e.g.
Chegg or the like) or getting help from anyone outside of this
class. If this code is violated, a zero grade is earned.
_______________________________________________________________________
Signature
If you do not provide your signature, you will earn a zero.
Student Name(s) Access ID
(e.g. kmm14)
CHEM 202 CS 3: Polar Acidic Reactions Dr. Masters
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FOCUS OF CASE STUDY 3: A Tale of Two Products!
In this Tale of Two Products, you will investigate
a synthetic scheme:
• To rationalize reaction outcomes
• To look for stereoisomer formation
• To predict specified reaction outcomes
• To evaluate structures, plus more!
• You write the end of this tale! J
Your task is to evaluate closely the reaction in this scheme, plus some other fun things to show-off your
knowledge and understanding!
I anticipate a best seller of a tale!
O
OH
H3O+ O
OH
HO
+
O
OH
HO
H2SO4 H2SO4
CHEM 202 CS 3: Polar Acidic Reactions Dr. Masters
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Question 1: STEP A!
GOAL of Question 1: Determine if compound A or
compound B is the major product of STEP A.
Let’s start this tale by answering leading questions.
TALE QUESTIONS:
Q1(a). List the two circled functional groups in the reactant: ________________________ and
___________________________________________________ (2 pts)
Q1(b). Describe what is changing in the reactant to become compound A or compound B. (3 pts)
Q1(c). What is the name of this reaction (STEP A)? ________________________________________________________________________ (2 pts)
Q1(d). Draw out an example of this reaction from our class notes. Reference the page # of the worksheet file. (3 pts)
O
OH
H3O+ O
OH
HO
+
O
OH
HO
compound A compound B
STEP A
O
OH
CHEM 202 CS 3: Polar Acidic Reactions Dr. Masters
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Q1(e). Draw the mechanisms of the formation of compound A and compound B. Be sure to include all electron-pushing a
ows,
intermediate structures, and formal charges where applicable. Start each mechanism with the reactant’s structure and H3O+. (6
pts each; 12 pts total)
Compound A’s Mechanism: Compound B’s mechanism:
CHEM 202 CS 3: Polar Acidic Reactions Dr. Masters
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Q1(f). From your mechanisms in part (e),
draw out each mechanism’s ca
ocation in
the appropriate box. (2 pts each; 4 pts total)
Q1(g). Draw the figure from the notes that shows the trend of relative stabilities of ca
ocations. Reference the page # from Unit
4 worksheet file, too! (4 pts)
Q1(h). Now, determine the ca
ocation above (in part f) that is most stable and the one that is least stable by circling your answers.
(2 pts each; 4 pts total)
Please explain your answers. (3 pts)
Ca
ocation from mechanism A
most stable / least stable
Ca
ocation from mechanism B
most stable / least stable
CHEM 202 CS 3: Polar Acidic Reactions Dr. Masters
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Q1(i). ( Markovnikov’s rule / Zaitsev’s rule ) (2 pts) predicts that the major product will come from the ca
ocation formed
in the mechanism of ( Compound A / Compound B ) (2 pts). (4 pts total)
Q1(j). Thus, the major product of this reaction is compound ________. (2 pts)
Q1(k). Circle the chiral centers in compound A:
(4 pts)
Q1(l). Draw all possible stereoisomers of compound A in
this empty box. (6 pts)
Q1(m). These stereoisomers are (check one): (3 pts)
______ enantiomers
______ diastereomers
______ constitutional isomers
Q1(n). The unit 3 worksheet gave two definitions of diastereomers. List them here and reference page #. (3 pts each; 6 pts total)
O
OH
HO
compound A
CHEM 202 CS 3: Polar Acidic Reactions Dr. Masters
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Question 2: STEP B
GOALS for Question 2:
• Determine and draw the
structures of compounds C and
D.
• Draw the complete mechanism
of STEP B: compound B to
compound D.
Q2(a). In a Fischer esterification reaction, the electrophile is a __________________________ ____________ functional group, and the
nucleophile is an _______________________ functional group ; this reactions forms an _________________________ functionality in the product.
Give an example of a Fischer esterification from the class notes below; reference the page #. (6 pts)
O
OH
HO
+
O
OH
HO
H2SO4 H2SO4
compound A compound B
compound C compound D
STEP B
CHEM 202 CS 3: Polar Acidic Reactions Dr. Masters
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Q2(b). Now, circle the two reactive atoms (elec and nuc) in both compound A and compound B given in the scheme on page 7.
(4 pts)
Q2(c). Are both Fischer esterification reactions in this scheme intra- or intermolecular reactions? Explain your answer. (4 pts)
Q2(d). Draw in the structures of compound C and compound D in the empty boxes in the scheme on page 7. (4 pts each; 8 pts
total)
Q2(e). Compound C is a newly formed ( five / six / seven ) membered ring. (2 pts)
Compound D is a a newly formed ( five / six / seven ) membered ring. (2 pts)
( Compound C / Compound D ) is more stable based on ring stability. (2 pts)
CHEM 202 CS 3: Polar Acidic Reactions Dr. Masters
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Q2(f). Draw the complete mechanism of STEP B – the reaction of compound B to compound D. Include all electron-pushing
a
ows and structures of all intermediates with formal charges where appropriate. (10 pts)