The document discusses the structure, bonding, and stability of carbocations, particularly highlighting the methyl cation's sp2 hybridized structure and empty 2p orbital. It explains that most carbocations are unstable, but their stability increases with alkyl group substitutions, with tertiary carbocations being the most stable. Additionally, it describes how the inductive effect helps in stabilizing positively charged carbons by dispersing the positive charge among adjacent atoms.

1. Structure, Bonding, and
Stability of Carbocations

2. Figure 4.8 Structure of methyl cation.
Carbon is sp2 hybridized.
All four atoms lie in same plane.

3. Figure 4.8 Structure of methyl cation.
Empty 2p orbital.
Axis of 2p orbital is perpendicular to plane of
atoms.

4. Carbocations
Most carbocations are too unstable to be
isolated.
When R is an alkyl group, the carbocation is
stabilized compared to R = H.
C
R R
R
+

5. Carbocations
C
H H
H
+
Methyl cation
least stable

6. Carbocations
C
H3C H
H
+
Ethyl cation
(a primary carbocation)
is more stable than CH3
+

7. Carbocations
C
H3C CH3
H
+
Isopropyl cation
(a secondary carbocation)
is more stable than CH3CH2
+

8. Carbocations
C
H3C CH3
CH3
+
tert-Butyl cation
(a tertiary carbocation)
is more stable than (CH3)2CH+

9. Figure 4.9 Stabilization of carbocations
via the inductive effect
positively charged
carbon pulls
electrons in  bonds
closer to itself
+

10. Figure 4.9 Stabilization of carbocations
via the inductive effect
positive charge is
"dispersed ", i.e., shared
by carbon and the
three atoms attached
to it
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