Zaitsev’s rule

Zaitsev’s Rule is a fundamental guideline in organic chemistry utilized to predict the predominant product formed during elimination reactions, specifically E1 and E2 reactions. The rule dictates that the most substituted alkene – the double bond bearing the greatest number of attached alkyl groups – will typically be the major product. This preference arises from the enhanced stability of more substituted alkenes, stemming from the stabilizing effect of hyperconjugation and the donation of electron density by adjacent alkyl groups. Consider the elimination of 2-bromobutane; the formation of 2-butene (the more substituted alkene) is overwhelmingly favoured. However, it’s important to note that steric hindrance from bulky bases or significant obstruction can sometimes disrupt this rule, potentially leading to the formation of a less substituted alkene as the major product.