Oxidation of alcohols and reduction of carbonyls Flashcards
How many carbons bonded to the carbon which a primary alcohol is bonded to?
1
How many carbons bonded to the carbon which a secondary alcohol is bonded to?
2
How many carbons bonded to the carbon which a tertiary alcohol is bonded to?
3
Why does it matter if an alcohol is primary secondary or tertiary?
Because you can predict the products in reactions
Three different reactions alcohols undergo
Combustion, elimination and oxidation
What do primary alcohols oxidise to form?
Aldehydes then carboxylic acids
What do secondary alcohols oxidise to form?
Ketones
What do tertiary alcohols oxidise to form?
Nothing. They don’t oxidise
What is the difference between an aldehyde and a ketone?
An aldehyde is at the end of the chain and a ketone is within the chain
What chemical do you react a primary alcohol with to make an aldehyde?
Potassium dichromate (VI)
Do you use distillation or a reflux reaction when oxidising a primary alcohol all the way to a carboxylic acid?
Reflux
colour change when potassium dichromate reduces a primary or secondary alcohol
Green to orange
What reducing agent is used in a non-aqueous solvent?
Lithium tetrahydridoaluminate
Chemical formula for Lithium tetrahydridoaluminate
LiAlH4
What reducing agent is used in an alcohol or water solution?
sodium tetrahydridoborate
Chemical formula for sodium tetrahydridoborate
NaBH4
Summary equation for reduction of an aldehyde to a primary alcohol
RCHO + 2[H] -> RCH2(OH)
Summary equation for reduction of ketone to a secondary alcohol
RCOR’ + 2[H] -> RCH(OH)R’
Summary equation for reduction of a carboxylic acid all the way to a primary alcohol
RCOOH + 4[H] -> RCH2OH + H2O
Does oxidation or reaction make more water molecules?
Reduction
