Skip to main content
Ch. 6 - The Reactions of Alkenes • The Stereochemistry of Addition Reactions
Bruice - Organic Chemistry 8th Edition
Bruice8th EditionOrganic ChemistryISBN: 9780135213711Not the one you use?Change textbook
Chapter 7, Problem 1

Draw the mechanism for the reaction of cyclohexene with HCl

Verified step by step guidance
1
Identify the reactants: cyclohexene is an alkene, and HCl is a strong acid.
Recognize that the reaction involves the addition of HCl across the double bond of cyclohexene.
Protonate the double bond: The π electrons of the double bond attack the hydrogen of HCl, forming a carbocation intermediate on the more substituted carbon.
Consider the stability of the carbocation: In this case, the carbocation forms on the more substituted carbon of cyclohexene, which is more stable.
Complete the reaction by having the chloride ion (Cl⁻) attack the carbocation, resulting in the formation of chlorocyclohexane.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
3m
Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Electrophilic Addition

Electrophilic addition is a fundamental reaction mechanism in organic chemistry where an electrophile reacts with a nucleophile, resulting in the formation of a more saturated product. In the case of cyclohexene and HCl, the double bond in cyclohexene acts as a nucleophile, attacking the electrophilic hydrogen in HCl, leading to the formation of a carbocation intermediate.
Recommended video:
Guided course
09:23
1,2 vs 1,4 Addition

Carbocation Stability

Carbocation stability is crucial in understanding reaction mechanisms involving electrophilic addition. Carbocations are positively charged species that can vary in stability based on their structure; tertiary carbocations are more stable than secondary or primary ones. In the reaction of cyclohexene with HCl, the formation of a more stable carbocation intermediate influences the pathway and products of the reaction.
Recommended video:
Guided course
05:58
Determining Carbocation Stability

Regioselectivity

Regioselectivity refers to the preference of a chemical reaction to yield one structural isomer over others when multiple possibilities exist. In the reaction of cyclohexene with HCl, the regioselectivity is determined by the stability of the carbocation formed during the reaction, leading to the major product being the more stable alkyl halide, which is influenced by the position of the double bond in cyclohexene.
Recommended video:
Guided course
05:09
Heck Reaction