Direct ortho-metallation process

摘要

In the present invention, there is disclosed a process of direct metalation useful for preparing phenyl tetrazoles of the general formula (II), which metalation process is characterized in that a starting compound is brought into reaction with a with a Grignard compound of the general formula Ri1MgX in the presence of a catalytic amount of a secondary amine of the general formula Ri2-NH-Ri3. The compounds of the general formula II are intermediates useful in the preparation of angiotensin II antagonists, such as tasosartan.