Markovnikov addition of HI to 2-methyl-2-butene involves: September 21, 2022 by 8i9x6 initial attack by an iodide ion. initial attack by an iodine atom. isomerization of 2-iodo-2-methylbutene. formation of a carbocation at C-2. formation of carbocation at C-3. See Answer formation of a carbocation at C-2.