As evidenced by H/D exchange with acidic zeolites, isoalkanes react readily at room temperature whereas linear alkanes do not. The observed regioselectivity of the exchange process demonstrates that the main factor controlling the reaction is not the accessibility to the acid sites, but the intrinsic reactivity of the alkane. The mechanism is best rationalized by classic organic chemistry involving carbocationic intermediates including the Markovnikov rule.

The existence of carbocationic intermediates in a zeolite environment even at room temperature is supported by hydride (and deuteride) transfers between isoalkanes as monitored ex situ by (13)C NMR.