AbstractThe preparation of lysergic acid [14C1]‐diethylamide is described. [14C1]‐Diethylamine was synthesised in three steps; sodium [14C1]‐acetate was treated with thionyl chloride giving [14C1]‐acetyl chloride which was reacted with ethylamine to give N‐ethyl‐[14C1]‐acetamide. Reduction of this amide with lithium aluminium hydride gave [14C1]‐diethylamine which on treatment with a lysergic...