Alcohols, Carbonyls and Acids

Question 1

Key features

Answer 1

Polar
High boiling points

Primary oxidised to aldehyde
Secondary to ketone

Form alkenes via elimination with H₂SO₄
- acid protonates OH, followed by dehydration then H+ elimination

Question 2

Aldehyde features

Answer 2

Via Tollen’s reagnt: Ag⁺→Ag
Via Fehling’s: Cu2+ →Cu₂O

Oxidise to carboxylic acids

Along with COOHs, reduce to primary alcohols via LiAIH₄ in dry ether

Also via NaBH₄ in ethanol (ketones reduce to secondary alcohols)

Question 3

OH →X substitution e.gs

Answer 3

Chlorination
CH₃OH + PCl₅ →CH₃Cl+POCl₃+HCl

Bromination
C₂H₅OH+HBr →C₂H₅Br + H₂O

Iodination
P+I₂ →Pl₃

Question 4

Alkoxides

Answer 4

OH + Na metal at RT

Form esters when boiled with COOH via H₂SO₄ catalyst