Metallation/reduction as a new approach to tritium labeling. The synthesis of [3H]ibogaine

A new method is presented for the tritiation of aryl compounds with tritium gas which is conducted on the underivatized substrate. Combined directed ortho metallation and facile reduction of the carbonpotassium bond affords incorporation of tritium at high specific activity under mild conditions. The metallation/reduction method is demonstrated for the preparation of [3H]ibogaine.