The carbon-magnesium bond in Grignard reagents is covalent but highly polar, with carbon pulling electrons from magnesium. Grignard reagents are highly reactive and react with proton sources, such as water and alcohols, to give corresponding hydrocarbons.

Grignard reagents are organo-metallic compounds, specifically alkyl magnesium halides (RMgX). They are prepared by the reaction of haloalkanes with magnesium metal in dry ether.

The Zaitsev rule predicts that pent-2-ene is the major product in the dehydrohalogenation of 2-bromopentane, as it has a greater number of alkyl groups attached to the doubly bonded carbon atoms compared to other potential products.

Russian chemist Alexander Zaitsev formulated the Zaitsev rule in 1875. The rule states that in dehydrohalogenation reactions, the preferred product is the alkene with the greater number of alkyl groups attached to the doubly bonded carbon atoms.

b-Elimination involves the removal of a hydrogen atom from the b-carbon and a halogen atom from the a-carbon in a haloalkane. This process forms an alkene as a product.