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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- + CH3OH methanol Suppose you were told that the above reaction was a substitution reaction but you were not told the mechanism. Evaluate the following categories to determine the reaction mechanism and then draw the structure of the major organic product. Type of alkyl halide: Type of nucleophile: Solvent: Is the product racemic? ***** • Use the wedge/hash bond tools to indicate stereochemistry where it exists. • If the reaction produces a racemic mixture, just draw one stereoisomer. Sn [1 ? ChemDoodleⓇ 1arrow_forward1. Reaction of 2,3-dimethyl-1-butene with HBr leads to an alkyl bromide, C6H13Br. On treatment of this alkyl halide with KOH in methanol, elimination of HBr occurs and a hydrocarbon that is isometric with the starting alkene is formed. What is the structure of this hydrocarbon and how do you think it is formed from an alkyl bromide? 2. 1-Octen-3-ol is a potent mosquito attractant commonly used in mosquito traps. A number of reactions, including hydrogenation, will transform 1-Octen-3-ol into a less effective molecule. Write a complete reaction equation for the hydrogenation of this alkenol.arrow_forwardDraw the structures of two alkenes that would react to form the haloalkane below upon addition of HBr. Your alkenes should be different regioisomers that yield the haloalkane as the major product without requiring rearrangement to occur.arrow_forward
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