Interpretation:
By drawing the resonance structures of the carbocation intermediates, among the two
Concept introduction:
The mechanism of addition of HBr to alkenes involves the formation of a more stable carbocation which is attacked by the Br- ion in the second step. Electron releasing groups in the
To predict:
Knowing the mechanism of HBr addition to alkenes and having an idea about the effects of various substituent groups on aromatic substitution, which of the two alkenes shown will react faster with HBr.
To explain:
The answer given by drawing the resonance structures of the carbocation intermediates.
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Organic Chemistry
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- Ethane reacts with chlorine (Cl2) in the presence of ultra-violet (UV) light, to produce 1-chloropropane (CH3CH2Cl) and hydrogen bromide (HCl). As shown in the equation below. CH3CH3 + Cl2 → CH3CH2Cl + HCl Describe the reaction mechanism of the reaction between ethane and chlorine to produce 1-chloroethane. The description should be detailed and must include the type of bond fission that takes place. You may sketch and insert suitable diagrams to aid your description if you wish. Would this reaction (question 34(c)) give a high yield of 1-chloroethanearrow_forwardEthane reacts with chlorine (Cl2) in the presence of ultra-violet (UV) light, to produce 1-chloropropane (CH3CH2Cl) and hydrogen bromide (HCl). As shown in the equation below. CH3CH3 + Cl2 → CH3CH2Cl + HCl Describe the reaction mechanism of the reaction between ethane and chlorine to produce 1-chloroethane. The description should be detailed and must include the type of bond fission that takes placearrow_forwardEthane reacts with chlorine (Cl2) in the presence of ultra-violet (UV) light, to produce 1-chloropropane (CH3CH2Cl) and hydrogen bromide (HCl). As shown in the equation below. CH3CH3 + Cl2 → CH3CH2Cl + HCl Describe the reaction mechanism of the reaction between ethane and chlorine to produce 1-chloroethane. The description should be detailed and must include the type of bond fission that takes place. You may sketch and insert suitable diagrams to aid your description if you wish.arrow_forward
- H3C CH3 H3C NA C→XT Br Br₂ CH₂Cl₂ H3C Electrophilic addition of bromine, Br₂, to alkenes yields a 1,2-dibromoalkane. The reaction proceeds through a cyclic intermediate known as a bromonium ion. The reaction occurs in an anhydrous solvent such as CH₂Cl₂. CH3 Br In the second step of the reaction, bromide is the nucleophile and attacks at one of the carbons of the bromonium ion to yield the product. Due to steric clashes, the bromide ion always attacks the carbon from the opposite face of the bromonium ion so that a product with anti stereochemistry is formed. Draw curved arrows to show the movement of electrons in this step of the mechanism. Arrow-pushing Instructions Br CH3 H3C CH3arrow_forwardDraw the structure of each product from the reaction of benzene with 2-chloro-1-methylcyclohexane using AlCl 3 as the catalyst and Identify the major product.arrow_forwardEthane reacts with chlorine (Cl2) in the presence of ultra-violet (UV) light, to produce 1-chloropropane (CH3CH2Cl) and hydrogen bromide (HCl). As shown in the equation below.CH3CH3+ Cl2→ CH3CH2Cl+ HClDescribe the reaction mechanism of the reaction between ethane and chlorine to produce 1-chloroethane. The description should be detailed and must include the type of bond fission that takes place. You may sketch and insert suitable diagrams to aid your description if you wish.arrow_forward
- The following alkyl halide can be prepared by addition of HBr to two different alkenes. Draw the structures of both (reddish-brown = Br).arrow_forwardAlkynes do not react directly with aqueous acid as do alkenes, but will do so in the presence of mercury(II) sulfate as a Lewis acid catalyst. The reaction occurs with Markovnikov regiochemistry, so the OH group adds to the more highly substituted carbon and the H adds to the less highly substituted carbon. The initial product of the reaction is a vinyl alcohol, also called an enol. The enol immediately rearranges to a more stable ketone via tautomerization. Draw curved arrows to show the movement of electrons in this step of the mechanism. Arrow-pushing Instructions -X티 Hö: H-O -CH3 -CH3 H30*arrow_forward2. The following carbocation is generated as an intermediate in the addition of H-Br to an alkene. Draw the structure of all possible alkenes that could have formed this intermediate.arrow_forward
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