Cleavage of Ethers Ethers are unreactive toward base,but protonated ethers can undergo substitution reactions with strong acids. Alcohol leaving group is replaced by a halide. Reactivity:HI HBr >HCI => Chapter 14 Chapter 14 17 Cleavage of Ethers • Ethers are unreactive toward base, but protonated ethers can undergo substitution reactions with strong acids. • Alcohol leaving group is replaced by a halide. • Reactivity: HI > HBr >> HCl =>