According to Saytzeff rule "In dehydrohalogenation reactions, the preferred product is that alkene which has the greater number of alkyl groups attached to the doubly bonded carbon atoms.
" For example: The dehydrohalogenation of 2-bromobutane yields two products 1-butene and 2-butene. Out of these 2-butene is the major product (80%) as it is more highly substituted and it is more stable.
