Answer to Question #304920 in Organic Chemistry for shamsa

Question

1. Show the structural formulae for the main product of each of the following

addition reactions between various alkenes and a hydrogen halide.

a) Ethene and hydrogen bromide

b) But-2-ene and hydrogen chloride

c) But-1-ene and hydrogen chloride

d) Propene and hydrogen iodide

e) 2-Methylbut-2-ene and hydrogen iodide

f) But-1-ene and hydrogen bromide where everything is pure

g) but-1-ene and hydrogen bromide in the presence of oxygen or

organic peroxides

Answer 1

a}when you mix ethene (a member of alkene group) and hydrogen bromide . Alkenes react with hydrogen bromide i n the cold. The double bond breaks and a hydrogen atom ends up attached to one of the carbons and a bromine atom to the other. In the case of ethene , bromoethane is formed

b)But-2-ene is an alkene because it contains a carbon-carbon double bond. It is being reacted with hydrogen chloride, a hydrogen halide. When an alkene reacts with a hydrogen halide, hydrohalogenation can occur. Hydrohalogenation is an addition reaction in which a hydrogen atom and a halogen atom are added to a molecul

c)So the major product formed from the reaction of but-1-ene with hydrogen chloride is 2-chlorobutane

d)What happens when propene reacts with hydrogen?

As with all alkenes, unsymmetrical alkenes like propene react with hydrogen bromide in the cold. The double bond breaks and a hydrogen atom ends up attached to one of the carbons and a bromine atom to the other. In the case of propene, 2-bromopropane is formed. The product is 2-bromopropane.