Chemistry Reference
In-Depth Information
3.17
E
a
ENERGY
products
Δ
H
reactants
REACTION COORDINATE
Because we are told that the reaction is slightly endothermic, the diagram is drawn
with the energy of the reactants slightly lower than the energy of the products (small
and positive
Δ
H
). Because we are told that the reaction is very slow, the diagram is
drawn with a large energy of activation (
E
a
).
3.18
A reaction energy diagram that fits the requirements stated in the problem is shown
below. Notice that the diagram is a composite of the two diagrams drawn for
Problems 3.17 and 3.16, in that order.
transition state #1
transitio
n state #2
E
a
#2
E
a
#1
intermediate
Δ
H
#1
ENERGY
reactants
Δ
H
#2
Δ
H
for overall reaction
products
REACTION COORDINATE
3.19
The boron adds to the
less
substituted carbon of the double bond, and, in the
oxidation, the boron is replaced by an OH group. Note that the acid-catalyzed
hydration of the same alkene would give the alcohol (CH
3
)
2
C(OH)CH
2
CH
2
CH
2
CH
3
instead, according to Markovnikov's rule.
