Chem 450—Advanced Organic Chemistry Exam 4

5. Give all possible products of the following reaction and indicate the major product (10
pts).
2
O NaOH
CF 3
EtOH, reflux
F 3C
6. Give a transition state explaining the stereochemistry of the enolate below (4 points).
O
O
LDA
THF
OH
N
H
O
Li
O
O
THF
CF 3
CF 3
THF
7. Explain the stereochemical outcome of the following reaction (4 points).
H
O
O
H
O
1. LDA/THF
2. BnBr
The enolate is attacked from the convex face opposite the aromatic ring as the H is
smaller. (The approach will also depend on the configuration next to the oxygen,
though this was not specified.)
+
and
+
Bn
H
OLi
F 3C
O
O
O
OH
O
O
CF 3
CF 3