A non‐exchange synthesis of tritium‐labelled tetrahydrocannabinols

Abstract

Abstract Tritium‐labelled (‐) ‐Δ 1 (6) and (‐) ‐Δ 1 ‐tetrahy irocannabinols at a specific activity of 607 mCi/mmole were synthesized by a non‐exchange method. The tritium was introduced by the catalytic reduction with tritium gas of an unsaturated precursor of dimethyl olivetol in hexafluorobenzene as a non‐exchanging solvent. Specifically labelled olivetol was subsequently used in the synthesis of (‐) ‐Δ 1 ‐tetrahydrocannabinol by an established method. The radiochemical purity of the product was shown to be greater than 98% by TLC, GLC, liquid scintillation counting and bioassay.