Podcast
Questions and Answers
In the E2 mechanism, what role does the reactant considered to be a nucleophile in the SN2 reaction play?
In the E2 mechanism, what role does the reactant considered to be a nucleophile in the SN2 reaction play?
- Attacking a beta hydrogen (correct)
- Forming the O-H bond
- Promoting the SN1 mechanism
- Breaking the C-Br bond
What does the formation of the O-H bond in the reaction lead to?
What does the formation of the O-H bond in the reaction lead to?
- Promotion of the SN1 mechanism
- Breaking of the C-Br bond
- Formation of the new C-C pi bond (correct)
- Transition state with four partial bonds
What type of kinetic behavior is observed in the reaction described?
What type of kinetic behavior is observed in the reaction described?
- First order
- Zero order
- Third order
- Second order (correct)
What is expected to happen to the rate of the reaction when changing from one halide to another?
What is expected to happen to the rate of the reaction when changing from one halide to another?
Which type of reaction is most prevalent when a strong base and a tertiary alkyl halide are present?
Which type of reaction is most prevalent when a strong base and a tertiary alkyl halide are present?
How many partial bonds are present in the transition state of the reaction described?
How many partial bonds are present in the transition state of the reaction described?
Why is there a departure from statistical expectation in the products of the elimination reactions described?
Why is there a departure from statistical expectation in the products of the elimination reactions described?
What does Zaitsev's Rule predict in terms of the favored product double bond in elimination reactions?
What does Zaitsev's Rule predict in terms of the favored product double bond in elimination reactions?
What is the meaning of 'E2' in the E2 mechanism reaction?
What is the meaning of 'E2' in the E2 mechanism reaction?
In the E2 mechanism, what determines the rate of the reaction?
In the E2 mechanism, what determines the rate of the reaction?
Which mechanism is closely related to substitution mechanisms?
Which mechanism is closely related to substitution mechanisms?
What does 'SN2' stand for in chemistry?
What does 'SN2' stand for in chemistry?
Which mechanism is closely related to the E2 mechanism?
Which mechanism is closely related to the E2 mechanism?
In the E1 mechanism, what is involved right after the formation of a carbocation?
In the E1 mechanism, what is involved right after the formation of a carbocation?
What determines the relative proportions of substitution and elimination products in the E1 mechanism?
What determines the relative proportions of substitution and elimination products in the E1 mechanism?
Which type of alkyl halide is unable to form a double bond in an E1 mechanism?
Which type of alkyl halide is unable to form a double bond in an E1 mechanism?
In which step of the E1 mechanism is the base not involved?
In which step of the E1 mechanism is the base not involved?
Which alkyl group structure change has a similar effect on both the SN1 and E1 mechanisms?
Which alkyl group structure change has a similar effect on both the SN1 and E1 mechanisms?
Flashcards
E2 Mechanism Role of Nucleophile
E2 Mechanism Role of Nucleophile
The nucleophile attacks a beta hydrogen in the E2 mechanism.
O-H Bond Formation Result
O-H Bond Formation Result
Formation of a new C-C pi bond.
E2 Reaction Kinetic Order
E2 Reaction Kinetic Order
Second order kinetic.
Halide Change Effect on Rate
Halide Change Effect on Rate
Signup and view all the flashcards
Strong Base & Tertiary Alkyl Halide Reaction
Strong Base & Tertiary Alkyl Halide Reaction
Signup and view all the flashcards
E2 Transition State Partial Bonds
E2 Transition State Partial Bonds
Signup and view all the flashcards
E2 Reaction Product Deviation
E2 Reaction Product Deviation
Signup and view all the flashcards
Zaitsev's Rule
Zaitsev's Rule
Signup and view all the flashcards
Meaning of E2
Meaning of E2
Signup and view all the flashcards
E2 Reaction Rate Determinant
E2 Reaction Rate Determinant
Signup and view all the flashcards
SN2 Relation to E2
SN2 Relation to E2
Signup and view all the flashcards
SN2 Meaning
SN2 Meaning
Signup and view all the flashcards
E1 Mechanism Post-Carbocation
E1 Mechanism Post-Carbocation
Signup and view all the flashcards
Product Proportion in E1 Mechanism
Product Proportion in E1 Mechanism
Signup and view all the flashcards
E1 Mechanism Incompatible Alkyl Halide
E1 Mechanism Incompatible Alkyl Halide
Signup and view all the flashcards
E1 Mechanism Base's Role
E1 Mechanism Base's Role
Signup and view all the flashcards
Alkyl Structure Effect on SN1 & E1
Alkyl Structure Effect on SN1 & E1
Signup and view all the flashcards
SN1 relation to substitution
SN1 relation to substitution
Signup and view all the flashcards
E1 mechanism
E1 mechanism
Signup and view all the flashcards
E1 reaction rate
E1 reaction rate
Signup and view all the flashcards
Study Notes
E2 Mechanism - Dehydrohalogenation
- In the E2 mechanism, a strong base attacks a beta hydrogen, leading to the formation of a double bond.
- The reactant acts as a base and attacks a beta hydrogen, releasing the CH bonding electrons to form the new C-C pi bond.
- The C-Br bond breaks at the same time to provide room for the new C-C pi bond to develop.
- The transition state has three partial bonds, including the alkyl halide and the base.
- The E2 mechanism is consistent with second-order kinetic behavior, where the concentrations of both the alkyl halide and the base are important in determining the rate of the reaction.
Factors Affecting the E2 Mechanism
- The rate of the E2 mechanism is affected by the type of halide, with RI > RBr > RCl > RF.
- The E2 mechanism is favored when there is a strong base and a tertiary alkyl halide.
- The combination of a strong base and a tertiary alkyl halide leads to a fast E2 elimination and a slow SN2 substitution.
E1 Mechanism
- The E1 mechanism involves the same first step as the SN1 mechanism, with dissociation of a halide ion to form a carbocation.
- The E1 mechanism continues with loss of a proton and the formation of a new pi bond.
- The rate of the E1 mechanism is determined by the rate of carbocation formation.
- The effect of changing alkyl group structure is the same as in the SN1 mechanism, with tertiary > secondary > primary.
- The E1 mechanism is likely to be used where no strong base is present, as the rate of the reaction does not depend on the base concentration.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
This quiz covers the similarities and differences between SN1, SN2, E1, and E2 mechanisms in organic chemistry. Learn about the key steps involved in each mechanism and how they relate to one another. Test your understanding of predicting products and reaction outcomes.
