which of the following belongs to +I group a) -oh b) -och3 c) -cooh d) -ch3
Answers
out of them : OH ,OCH₃,COOH show -I effect and -CH₃ shows +I effect ,
Explanation:
There are many electron displacement reactions that are shown in organic compounds .
That is mainly of four types :
- Inductive effect
- Resonance effect
- Hyper conjugation effect
- Electromeric effect
Inductive effect
It is a permanent effect that arises when some electron releasing or withdrawing group is attached to chain of alkane.
In this :
C-C₄-C₃-C₂-C₁-X (x is electro-negative )
If X is electronegative, it will attract the shared pair electrons more towards itself. As a result, X will acquire partial negative charge and C₁ will acquire partial positive charge.
Now this positive charge of C₁ will attract electrons of C₁ – C₂ bond. As a result, some of the positive charge on C₁ will be reduced and on C₂ it will develop.
This effect happens only till 4th carbon as after 4th carbon the magnitude of charge is almost nil.
• So, we can define it as “the displacement of electrons along the saturated carbon chain due to presence of polar covalent bond at the end of the chain. “
It is of two types
o -I effect
o +I effect
-I effect
It is shown when electron withdrawing group is attached to the carbon chain.
That is Bromide ion ,hydroxide ion etc
+I effect
It is shown when electron releasing group is attached to carbon chain .
Example – Alkyl groups.
“More the number of alkyl groups , more is the +I effect.”