Tautomerism in alkenes Why doesn't but-2-ene exhibit tautomerism like alkenols?
By transfer of 1 hydrogen from terminal CH₃ to the middle carbon and forming a double bond between the two?
In order for tautomerism to occur, the enol must be deprotonated, so as to allow the negative charge to come down, kick the pi bond of the C=C bond, which will bond to a proton. Hydrogen atoms on oxygen are much more acidic than hydrogens on carbons because of the electronegativity differences between O and H. Thus, the deprotonation does not happen in alkenes.