Page 1
Name:_________________Discussion TF: _____________ BU ID:___________Discussion section:_________
Homework #11 Fall 2019-Due Friday, December 13 by 5 pm in the boxes outside SCI 299
Please make sure the put your name, discussion TF and BU ID on the top of this page. This problem set must be
printed out and answers directly written on the printout.
No late homework is accepted.
1. Molecule
2
was prepared via treatment of molecule
1
with sulfuric acid.
2
is formed via a carbocation
rearrangement.
Provide a complete curved arrow mechanism for the most straightforward conversion of
1
to
2
.
(You
may use
+
B-H as generic acid and B: as a generic base).
OH
OH
Ph
O
Ph
H
H
2
SO
4
OH
OH
Ph
H
B
OH
O
Ph
H
H
OH
Ph
OH
Ph
O
Ph
H
H
O
Ph
H
B
1
2
2. a) When compound
3
is treated with methanol it forms a carbocation. Draw the carbocation that would be
formed and the best resonance structure of the compound.
b) Below are different conditions that can be used for an S
N
1 mechanism. In each pair circle the molecule that
would provide a faster S
N
1. If they are equal rates, circle both.


Page 2
Name:_________________Discussion TF: _____________ BU ID:___________Discussion section:_________
3. For the following transformations draw the product in the box below. Draw only one stereoisomer in the box
if there is more than one. On the right side check the box(es) that corresponds to the product obtained from the
reaction, if one is provided. Only organic products need to be provided.
a)
O
HO
O
H
2
SO
4
Br
H
Cl
H
Cl
KO
t
Bu
O
b)
Ph
Br
ONa
Ph
KO
t
Bu
Ph
OH
1) TsCl, pyridine
2) NaCN
CN
1 enantiomer
(1 chiral compound)
1:1 mix of
enantiomers
mixture of
diastereomers
achiral
X
1 enantiomer
(1 chiral compound)
1:1 mix of
enantiomers
mixture of
diastereomers
achiral
X
Br
OH
O
23 °C
1 enantiomer
(1 chiral compound)
1:1 mix of
enantiomers
mixture of
diastereomers
achiral
X
1 enantiomer
(1 chiral compound)
1:1 mix of
enantiomers
mixture of
diastereomers
achiral
X
1 enantiomer
(1 chiral compound)
1:1 mix of
enantiomers
mixture of
diastereomers
achiral
X
Br
2) NaN
3
1) KI
H
H
H
O
N
3
H
H
H
c)
d)
e)
f)


Page 3
Name:_________________Discussion TF: _____________ BU ID:___________Discussion section:_________
4. Upon treatment of strong base
4
undergoes an E2 elimination. Answer the following questions about this
elimination.
5. When cyclohexane
5
is treated with a strong base it undergoes an E2 elimination. Answer the following
questions about the reaction below.
a) Draw the structure of the favored product for the E2 reaction
b) Draw the two chair conformations for cylcohexane
5
. (Make sure to draw out all groups including
hydrogens.)
c) Put a square around the most stable chair and circle the reactive conformation.
d) When cyclohexane
6
is heated to high temperatures under vacuum a variety of products are formed with
7
and
8
being predominant. Explain why the reaction outcome is different than that above.


Pay $2 or upload 3 study materials to unblur this document.