Why -OR has more -I effect than -OH

Thread starter Frigus
Start date Oct 18, 2019

In summary, the -I effect of a substituent is determined by its size and electronegativity. The larger and less electronegative -OR group has a greater -I effect than the -OH group. The size of a substituent also plays a role, as larger substituents have a greater electron-withdrawing ability. Other factors, such as the nature and position of the substituent, can also impact the reactivity of -OR and -OH groups. The -I effect can greatly influence the chemical properties of these groups, making -OR groups more reactive and potentially altering the stability and structure of molecules.

Oct 18, 2019

Frigus

as -OR group is attached with alkyl group, alkyl group increases electron density on the atom with which it is attached but its minus I effect is more than the -OH which has only H

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Oct 21, 2019

TeethWhitener

Science Advisor

Gold Member

Do you have a reference? I can't imagine the difference is very large.

1. Why does -OR have more -I effect than -OH?

-OR has more -I effect than -OH because the oxygen atom in the -OR group is more electronegative than the oxygen atom in the -OH group. This causes the electrons in the -OR group to be more tightly held, resulting in a stronger electron-withdrawing effect.

2. What is the difference between -OR and -OH?

The main difference between -OR and -OH is the presence of a carbon atom in the -OR group. In -OH, the oxygen atom is directly bonded to a hydrogen atom, while in -OR, the oxygen atom is bonded to a carbon atom which is then bonded to a hydrogen atom.

3. How does the -I effect of -OR and -OH affect the reactivity of a molecule?

The -I effect of -OR and -OH makes the molecule more electron-deficient, making it more reactive. This is because the withdrawal of electrons by these groups creates a positive charge on the carbon atom, making it more susceptible to attack by nucleophiles.

4. Can the -I effect of -OR and -OH be reversed?

Yes, the -I effect of -OR and -OH can be reversed by the presence of strong electron-donating groups. These groups, such as -NH2 and -OCH3, can donate electrons to the carbon atom, reducing its positive charge and weakening the -I effect of -OR and -OH.

5. How does the length of the carbon chain in -OR affect its -I effect?

The length of the carbon chain in -OR does not significantly affect its -I effect. The electronegativity of the oxygen atom is the main factor that determines the strength of the -I effect, not the length of the carbon chain.