Which of the following halides do NOT undergo SN1 or SN2 substitution readily under ordinary conditions?

Vinylic and aryl halides have the halogen on an $s{p}^2$ carbon: the C-Cl bond is shorter and stronger (partial double bond character by resonance), the cation would be unstable and backside attack is blocked. 1-Chlorocyclohexene is a vinylic halide. Allyl chloride has an $s{p}^3$ carbon bearing Cl and is reactive in both mechanisms.