Concept explainers
(a)
Interpretation:
The carbon atom must be identified which is migrating and the mechanism for carbocation rearrangement must be drawn.
Concept Introduction:
For carbocation rearrangements, there should be some driving force. One moderately stable carbocation can rearrange to a more stable carbocation or release angle strain.
(b)
Interpretation:
The diastereomeric carbocation which is not formed must be drawn.
Concept Introduction:
When out of the two diastereomers, only one is formed the reaction is called diastereoselective.
(c)
Interpretation:
One driving force must be suggested for the rearrangement of one tertiary carbocation to another tertiary carbocation.
Concept Introduction:
For carbocation rearrangements, there should be some driving force. One moderately stable carbocation can rearrange to a more stable carbocation or release angle strain.
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