Electrophilic addition

• Reaction with hydrogen halides

  The mechanism of alkenes that form Halogenalkanes is electrophilic addition

  • The double bond would break and it's electrons would transferred to the slightly positive hydrogen on the hydrogen halides.
  • So the bond between the hydrogen and halide would transfer to halide
  • Then a carbocation would form.
  • There can be 1° , 2° and 3° but the carbocation that is most likely to form in the most stable one which is the 3° and the least is 1°. This product is the major product
  • The halide would then be attracted to the carbon that's missing a bond
• Reaction with bromine water


  The mechanism for the alkene to react with halide compounds to form dihaloalkanes is electrophilic addition

  
• Reaction between alkenes and sulfuric acid

  The mechanism for alkenes to react with sulfuric acid to form alkyl Hydrogensulphate is electrophilic addition

  • The sulphuric acid needs to be concentrated

  
• Alkenes to alcohols

  Alkenes go through electrophilic addition to produce alcohol

  • Reagent is H2O
  • Has a H3PO4 catalyst

  The double bond from the alkenes goes to a H+ ions from the catalyst which breaks the bond. There's a missing bond on the carbon so the pair of electrons on the oxygen on the water goes to the carbon. Now there's too many bonds on the oxygen so the bond from a hydrogen goes to it and that is used to reform catalyst