When a sample of phenol is treated with an excess of bromine water (), it undergoes rapid electrophi — Alcohols Phenols and Ethers Chemistry Question
Question
When a sample of phenol is treated with an excess of bromine water ($Br_2 / H_2O$), it undergoes rapid electrophilic aromatic substitution to form a characteristic white precipitate. Exactly how many atoms of bromine ($Br$) are covalently bonded to the aromatic ring in a single molecule of this major final product?
💡 Solution & Explanation
Phenol is highly activated. In an aqueous (polar) medium, the intermediate phenoxide ion forms, maximizing ring activation. Bromination occurs concurrently at all available electron-rich ortho and para positions, resulting in 2,4,6-tribromophenol, which contains exactly 3 covalently bonded bromine atoms.