The correct order of IR stretching frequency of the $\mathrm{C=C}$ in the following olefins is(I)(II)(III)
(a)I $>$ II $>$ III
(b)II $>$ III $>$ I
(c)III $>$ II $>$ I
(d)III $>$ I $>$ II
Answer
Answer: C ✓ checked by 4AB · confidence high
Explanation
Exocyclic C=C stretching rises with ring strain: methylenecyclopropane ≈ 1780, methylenecyclobutane ≈ 1680, methylenecyclohexane ≈ 1650 cm⁻¹. III > II > I (c).