Alcohol
What is it? Core information
Alcohol – Compounds with one or more -OH
groups attached to a hydrocarbon group.
Examples of Alcohol: Cholesterol, menthol,
ethanol, methanol.
o General formula of Alcohol: CnH2n + OH
o Alkyl groups (methyl, ethyl, etc) are slightly
positive
o Alcohol groups are slightly negative
o High boiling points
o Alcohols are not so nucleophilic, their charge
is neutral and the oxygen in the hydroxyl
group holds tightly onto its electron pair.
o Alcohols are weakly acidic compounds with
pKa of around 16.
o If we deprotonate an alcohol, alkoxide is
produced, the negatively charged conjugate
base which is an excellent nucleophile.
o Alkoxide can help make different oxygen-
containing organic compounds such as
ethers.
o Ethers have an oxygen concerted to two alkyl
or aromatic carbons.
, o Hydroxyl groups in alcohols are poor leaving
groups because the hydroxide ion is a strong
base.
o There is a great demand for alcohols in our
industry, we use them to make antifreeze for
our engines
o Also used an antiseptic to disinfect the skin
o Hand sanitiser that works without water
contains alcohols
o Ethanol is a ingredient in alcoholic drinks and
is a important antiseptic
o Alcohols can also be used as fuels,
preservatives (prevents decay) and solvents
There are three categories of Alcohols:
Primary
Secondary
Tertiary
These are based on the position of the OH on
the chain
Alcohols react differently (relative reactivity)
depending on the group they are in (1 °, 2 °, 3 °).
What is it? Core information
Alcohol – Compounds with one or more -OH
groups attached to a hydrocarbon group.
Examples of Alcohol: Cholesterol, menthol,
ethanol, methanol.
o General formula of Alcohol: CnH2n + OH
o Alkyl groups (methyl, ethyl, etc) are slightly
positive
o Alcohol groups are slightly negative
o High boiling points
o Alcohols are not so nucleophilic, their charge
is neutral and the oxygen in the hydroxyl
group holds tightly onto its electron pair.
o Alcohols are weakly acidic compounds with
pKa of around 16.
o If we deprotonate an alcohol, alkoxide is
produced, the negatively charged conjugate
base which is an excellent nucleophile.
o Alkoxide can help make different oxygen-
containing organic compounds such as
ethers.
o Ethers have an oxygen concerted to two alkyl
or aromatic carbons.
, o Hydroxyl groups in alcohols are poor leaving
groups because the hydroxide ion is a strong
base.
o There is a great demand for alcohols in our
industry, we use them to make antifreeze for
our engines
o Also used an antiseptic to disinfect the skin
o Hand sanitiser that works without water
contains alcohols
o Ethanol is a ingredient in alcoholic drinks and
is a important antiseptic
o Alcohols can also be used as fuels,
preservatives (prevents decay) and solvents
There are three categories of Alcohols:
Primary
Secondary
Tertiary
These are based on the position of the OH on
the chain
Alcohols react differently (relative reactivity)
depending on the group they are in (1 °, 2 °, 3 °).
