Transmetallation Negishi protocol

The DoM C—C cross-coupling was notably employed in the synthesis of telmisartan 75, an angiotensin II receptor antagonist [173]. The reaction pathway is based on a one-pot protocol employing sequential metalation, transmetalation to zincate, and Negishi transition metal-catalyzed cross-coupling. At final step, the oxazoline DMG is removed by hydrolysis to afford the expected carboxylic acid product 75 (Scheme 26.22). 

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