Concept explainers
(a)
Interpretation: Potential-energy versus reaction-coordinate diagrams for the two propagation steps in mechanism for monobromination of pentane should be sketched.
Concept introduction: The mechanism for monobromination comprises of three stages illustrated as follows:
Step1: Initiation via homolytic cleavage of
Step2: Propagation: In first of the propagation steps bromine radical from step 1 abstracts hydrogen radical from methane as follows:
In subsequent propagation step methyl radical abstracts
Step3: Termination: Radicals generated in propagation steps get quenched upon combination with one another illustrated as follows:
(b)
Interpretation:The locations of the transition states and whether each transition state is early or late should be indicated.
Concept introduction:In general, the exothermic reactions are characterized by an early transition state while the endothermic reaction is characterized by a late transition state.
In the former case, the transfer of
(b)
Interpretation: The similar plot for reaction of pentane with
Concept introduction: In general the exothermic reactions are characterized by an early transition state while the endothermic reaction is characterized by a late transition state.
In the former case, the transfer of
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Organic Chemistry: Structure and Function
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