Massachusetts Institute of Technology
5.13, Fall 2006
Problem Set #6
Due: November 13, 2006, 12:00 PM
1. Show how you would accomplish the following syntheses in good yields.
NH2
H
N
a)
H
O
O
HO
CH2NH2
b)
2. Propose a synthetic sequence to convert the given lactone into the following
amine.
HO
O
N
O
3. Show how you would synthesize chlorpheniramine, a powerful antihistamine
used in several decongestants, from the given carboxylic acid.
O
N
OH
Cl
N
N
Cl
1
Massachusetts Institute of Technology
5.13, Fall 2006
4. Show how you would carry out the following transformation in which the ester
function at the lower left of the molecule is converted into a hydroxy group but the
one at the upper right is preserved.
H3 C
OCH3
OCH3
H3 C
O
O
O
H3 C
O
HO
5. Propose reasonable mechanisms for the following reactions.
a)
Ph C N + PhMgI
H2 O
O
A
+
Ph
Ph
NH4+
O
OH H3O+/H2O
OH
b)
O
H3O+/H2O
O
O
O
6. a) When methanol containing an oxygen-18 isotope is treated with
benzenesulfonyl chloride in pyridine, a product A is formed. When A is treated
with sodium hydroxide, methanol is formed again along with another product B,
and the methanol contains none of the isotope. Identify products A and B.
+
CH3OH
*
O
Ph S Cl
O
pyridine
A
NaOH
CH3OH + B
b) When methanol containing an oxygen-18 isotope is treated with acetyl
chloride in pyridine, a product C is formed. When C is treated with sodium
hydroxide, methanol is formed again along with another product C, and the
methanol contains all of the isotope. Identify the products C and D.
O
+
CH3OH
H3C C Cl
*
pyridine
C
NaOH
CH3OH
* + D
2