How many of the following substituent groups generally possess a higher migratory aptitude than a si — Reaction Mechanism Chemistry Question
Question
How many of the following substituent groups generally possess a higher migratory aptitude than a simple methyl group ($-CH_3$) during a standard carbocation rearrangement? List: Hydride ($-H$), Phenyl ($-C_6H_5$), Ethyl ($-CH_2CH_3$), Isopropyl ($-CH(CH_3)_2$), tert-Butyl ($-C(CH_3)_3$).
💡 Solution & Explanation
The standard migratory aptitude for carbocation rearrangements, driven by the ability to stabilize the transition state through electron donation, follows the order: $Hydride > Phenyl > 3^\circ Alkyl > 2^\circ Alkyl > 1^\circ Alkyl > Methyl$. Comparing the given list to a methyl group, all five listed substituents (Hydride, Phenyl, Ethyl, Isopropyl, and tert-Butyl) have a higher migratory aptitude.