A Scalable Process for the Synthesis of 2-Methyl-1,4,5,6-tetrahydroimidazo[4,5-<i>d</i>][1]benzazepine Monohydrate and 4-[(Biphenyl-2-ylcarbonyl)amino]benzoic Acid: Two New Key Intermediates for the Synthesis of the AVP Antagonist Conivaptan Hydrochloride
the “side chain” precursor molecule, which is the second key intermediate. These advances revolve around the acylation of an unprotected aminobenzoicacid and subsequent high-yield telescoped processes for the synthesis of 4-[(biphenyl-2-ylcarbonyl)amino]benzoicacid. This novel method leads to a 4-fold increase in the overall yield of the target materials, circumvents the restricted synthetic intermediates