Oils containing highly unsaturated acids like linolenic acid undergo oxidation in air. This reaction, called oxidative rancidity, is accelerated by heat, explaining why saturated fats are preferred for deep fat frying.

(a) Molecular oxygen is a diradical. What type of mechanism does a diradical suggest for this reaction?
(b) Why is the position shown (C-11) a likely site for attack?
(c) Propose a plausible mechanism for this reaction.
(d) BHA and BHT are antioxidants added to foods to interrupt the oxidation mechanism. Suggest how these molecules might work as antioxidants.

Transcribed Image Text:

COOH ↓0-0 O-O O-OH он он C(CH3)3 (CH3)3C CH3 BHT OCH3 BHA