Category: Markovnikov`s Rule

What does Markovnikov’s rule predict? Markovnikov’s rule predicts the regiochemistry of the reaction when a protic acid (usually denoted by HX) is added to an unsymmetrically substituted alkene. It predicts that the halide part of the protic acid preferentially attaches itself to highly substituted carbon atoms whereas the hydrogen component of the protic acid preferentially…

When alkenes are treated with borane (BH3) in the presence of hydrogen peroxide or sodium hydroxide, an alcohol is obtained as the final product. In this electrophilic addition reaction, the boron atom acts as an electrophile. This reaction does not obey Markovnikov’s rule and can, therefore, be classified as an anti-Markovnikov reaction. 

The Hydration of Alkenes When alkenes are treated with certain aqueous acids (usually sulfuric acid), the resulting electrophilic addition reaction yields an alcohol as the product. The regioselectivity of such reactions can be predicted by Markownikoff’s rule. Therefore, these reactions can be classified as Markovnikov reactions. In the hydration of alkenes, the H+ ion acts as an electrophile…

To understand this mechanism, let us consider the same example illustrated earlier, i.e. the addition reaction of hydrobromic acid with propene. The Mechanism of Markovnikov’s rule can be broken down into the following two steps. Step 1 The alkene is protonated and it gives rise to the more stable carbocation as shown below. From the illustration…

Markovnikov’s Rule, also known as Markownikoff’s rule, can be used to describe the outcome of some chemical addition reactions. The Russian chemist Vladimir Vasilyevich Markovnikov first formulated this rule in 1865. What is Markovnikov’s Rule? When a protic acid (HX) is added to an asymmetric alkene, the acidic hydrogen attaches itself to the carbon having a…