Electromeric effect
General Organic Chemistry (GOC) · Chemistry
Study notes
How does the electromeric effect direct HBr addition to propene? Step 1: H⁺ (electrophile) approaches the C=C π bond. Step 2: π electrons shift toward H⁺ (+E effect) — the bond polarizes temporarily. Step 3: H⁺ bonds to the carbon that leaves the more stable carbocation (Markovnikov). Step 4: Br⁻ then attacks the carbocation. Temporary polarization → permanent product!