Question

Which underlined proton (or sets of protons) has the greater chemical shift (that is, the higher frequency signal)?

Short answer

The protons with the greater chemical shift are underlined below.

Step-by-step solution

Step-by-Step SolutionStep 1: Electronegativity

Electronegativity is the electron attracting power of an atom.Its chemical shift is greater if a proton is attached to a higher electronegative atom. The electronegativity of chlorine is higher than bromine, so the chemical shift of the proton attached to chlorine is higher.

Position of protons

If a proton is near an electronegative atom,such asfluorine or chlorine, its chemical shift is higher.

Hence, the protons with a greater chemical shift are underlined below.

Underlined protons have a greater chemical shift