General organic chemistry

How is electron density related to charge and size?

Electron density ↑ with higher charge, ↓ with larger size

What happens to reactants and reagents before forming products?

They go through a transition state or reactive intermediate.

What is electronegativity?

it’s the tendency of an atom to attract a shared electron pair in a covalent bond.

Arrange in descending order of electron density: A⁻, A, A⁺

A⁻ > A (neutral) > A

What are electronic displacement effects?

shifting of electrons in a molecule due to different influences.

How many types of electronic displacement effects are there?

Permanent effects and Temporary effects.

Which effects are permanent electronic effects?

Inductive effect, Mesomeric effect, Hyperconjugation.

Which effect is a temporary electronic effect?

Electromeric effect.

What is the inductive effect?

A permanent shift of electron density along a chain of sigma bonds due to difference in electronegativity between atoms or groups.

Through which bonds does inductive effect operate?

Sigma (σ) bonds only.

is inductive effect distance dependent?

Yes it is neglected after 3rd carbon

What is +I (positive inductive) effect?

When an electron-donating group is attached, pushing electron density toward the chain.

What charge develops on adjacent atoms in +I effect?

Adjacent atoms develop a partial negative charge (δ⁻).

Order of +I effect (strongest → weakest)?

–O⁻

–COO⁻

–C(CH₃)₃

–CH(CH₃)₂

–CH₂CH₃

–CH₃

–D

–H

What is −I (negative inductive) effect?

When an electron-withdrawing group pulls electron density away from the chain.

What charge develops on adjacent atoms in −I effect?

djacent atoms develop a partial positive charge (δ⁺).

Order of −I effect (strongest → weakest)?

NR₃⁺

SR₂

NH₃⁺

NO₂

SO₂R

CN

CHO

COOH

F

Cl

Br

I

OR

OH

Alkyne

NH₂

C₆H₅

Alkene

H

What is the first major application of inductive effect?

To compare acidic strength of aliphatic carboxylic acids.