AS ORGANIC CHEMISTRY REASCTIONS Flashcards
Number of ways to convert an alkene to halogenoalkane
- Addition of a hydrogen Halide
2. Addition of halogen
Addition of hydrogen halides to alkenes
- Electrophilic additio
- Bubble through a concentrated solution
- Room temperature
- Major an minor products
Addition of Halogen
- Addition reactions
- Free Radical substitution
- Room temperature
- Decolorisation -> good test for C=C
What is the way that a halogenoalkane can be converted to an alkene?
Elimination reactions
Describe the elimination reaction of a halogenoalkane to alkene
- Done under ethanolic NaOH
- involves the loss of an HX group
How can an alkene be converted to an alkane?
By the addition of Hydrogen
Addition of Hydrogen to an alkene
- Addition reaction
- Nickel Catalyst
2 ways that an alkene can be converted to an alcohol
- Addition of Steam
2. Cold dilute acidified manganate solution (VII)
Describe the addition of steam in making an alcohol from an alkene.
- Addition reaction
- Catalyst: Conc Phosphoric acid
- 330 Degrees Celsius
- 6 MPa pressure
Cold Acidified Manganate reaction of Alkenes
- Makes Diols
- Dilute solution fo KMnO4
- Goes from purple to colourless
- Room temperature/Pressure
How can an alcohol be made into an alkene?
- Dehydration reaction
Dehydration of Alcohol
- Makes Alkene
- Elimination reaction
- Loss of water
- Catalyst: Hot Aluminium Oxide Powder
Aldehyde from Alkene
Oxidation with KMnO4
Oxidation of Alkenes under distillation
- Produces Aldehyde
- Hot Concentrated KMnO4
Carboxylic acid from aldehyde
Oxidation with concentrated KMnO4 under reflux
Aldehyde to Alcohol
Reduction.
Oxidation of Alcohol to Aldehyde
- Acidified (H2SO4) K2Cr2O7
- Orange -> Green
- warming required
- primary alcohol
- Distill to prevent carboxylic acid formation
Alcohol to Aldehyde
Oxidation
Reduction of Aldehyde to Alcohol
- Reducing agent: LiAlH4 / NaBH4
- if LiAlH4, then under dry ether
- if NaBH4, then (NaOH)aq + warm
- Primary alcohol