2,4-Dimethoxybenzyl Group for the Protection of Tetrazole: An Efficient Synthesis of Olmesartan Medoxomil through C–H Arylation

Abstract

The 2,4-dimethoxybenzyl (DMB) group was found to be effective for protecting tetrazoles. The DMB group is inert to various conditions, including those for ruthenium-catalyzed C–H arylation, but is readily cleaved under mild conditions. The use of a DMB protecting group permitted a synthesis of highly functionalized olmesartan medoxomil in a few steps.

Key words

protecting groups - arylations - heterocycles - biaryls - drugs - tetrazoles

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