Zaitiff's rule is a key principle in organic chemistry that applies during elimination or dehydration reactions of alcohols. This rule is particularly relevant when the neighboring carbons of the alcohol have differing numbers of hydrogen atoms. According to Zaitiff's rule, the hydroxyl (OH) group is removed from the alcohol carbon, while a hydrogen atom is removed from the neighboring carbon that has fewer hydrogen atoms.

For instance, consider an alcohol with two neighboring carbons: one with two hydrogens (CH₂) and the other with three hydrogens (CH₃). Following Zaitiff's rule, the hydrogen atom would be lost from the carbon with two hydrogens, as it has fewer hydrogens available for elimination. Consequently, the OH group is also lost from the alcohol carbon, resulting in the formation of a double bond between the two neighboring carbons to satisfy the tetravalency of carbon.

This process ensures that the correct alkene is produced at the end of the reaction, highlighting the importance of Zaitiff's rule in guiding the formation of alkenes from alcohols. By adhering to this rule, chemists can predict the outcome of dehydration reactions more accurately, leading to the desired products.