How are electrons used in acid and basic medium ?
The mechanism steps are : Lewis acid forms a polar coordinate with a basic site on the reactant ( such as an O or N ) Its electrons are drawn towards the catalyst , thus activating the reactant The reactant is then able to be transformed by a substitution reaction or addition reaction The product dissociates and catalyst is regenerated Common Lewis acids include aluminium chloride , ferric chloride and boron trifluoride .