3.4 Alkenes Flashcards
Why is there no free rotation around C=C bond
Define an electrophile
An electron-pair acceptor
Draw electrophilic addition mechanism with HCl or HBr as the reagent
What is the electrophile in this reaction?
Electrophile : HBr
Btw this can also happen with Br2 or Cl2
Why are tertiary carbocations more stable than primary carbocations
There is a greater positive inductive effect from three alkyl groups in tertiary carbocations compared to two alkyl groups in secondary carbocations
Explain why 2-bromopropane is the major product formed compared to 1-bromopropame
- 2-bromopropane is made from a secondary carbocation
- 1-bromopropame is made from a primary carbocations
- Secondary carbocations are more stable due to the positive inductive effect of two alkyl groups compared to one
Bromine reacts with alkenes even though it is a non-polar molecule. Explain why bromine molecules react with the double bonds in alkenes
- C=C bond is electron rich
- and induces a dipole in Br2
- Delta plus Br2 is attracted to C=C double bond
How to test for alkenes
Add bromine water
Solution goes from orange to colourless
Draw electrophilic addition mechanism when Sulfuric acid is the reagent
Show how akyl hydrogen sulfates can be reacted with water to produce an alcohol
It is possible to turn alkenes directly into alcohols by reacting them with water. State reagent and conditions
Reagent : H2O
Condition : H3PO4 Catalyst
Name compound
Draw polymer of this molecule
Condition for electrophilic addition (alkene haloalkane)
Hot & ethanolic solvent
Draw elimination mechanism
C
Name type of reaction that occurs when bromine water reacts with the hydrocarbon
Electrophilic addition
