The addition of nucleophiles to the carbon-carbon double bond of an α , β unsaturated aldehyde or ketone and the regioselectivity of the addition has to be accounted. Concept introduction: Electrophilic addition reaction is an addition reaction where in a chemical bond , a Π bond is Brocken and two new σ bonds are formed, the substrate of an electrophilic addition reaction must have a double bond or triple bond. Carbocation: The carbon ion that bears a positive charge on it. Nucleophile: donates pair of electrons to positively charged substrate resulting in the formation of chemical bond. Electrophile: accepts pair of electrons from negatively charged substrate results in chemical bond formation. Consider elimination reaction where alkenes are formed when alkyl halides are treated with bases via eliminating one β-proton and one α-halo group of the alkyl halide. The product of the elimination reaction is depends upon the β-positions of alkyl halide. If the β-positions are identical and the products formed are also identical. If the β-positions are different and the products formed are also different. This means the double bond can form in two different regions so this type of reaction is called regioselective and the products are called as regiochemical outcomes.

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Chapter 16, Problem 16.69P

Interpretation Introduction

Interpretation: The addition of nucleophiles to the carbon-carbon double bond of an α,β unsaturated aldehyde or ketone and the regioselectivity of the addition has to be accounted.

Concept introduction:

Electrophilic addition reaction is an addition reaction where in a chemical bond, a Π bond is Brocken and two new σ bonds are formed, the substrate of an electrophilic addition reaction must have a double bond or triple bond.

Carbocation: The carbon ion that bears a positive charge on it.

Nucleophile: donates pair of electrons to positively charged substrate resulting in the formation of chemical bond.

Electrophile: accepts pair of electrons from negatively charged substrate results in chemical bond formation.

Consider elimination reaction where alkenes are formed when alkyl halides are treated with bases via eliminating one β-proton and one α-halo group of the alkyl halide.

The product of the elimination reaction is depends upon the β-positions of alkyl halide. If the β-positions are identical and the products formed are also identical. If the β-positions are different and the products formed are also different. This means the double bond can form in two different regions so this type of reaction is called regioselective and the products are called as regiochemical outcomes.

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