This invention is directed to a process for manufacturing 2-[(3,5-difluoro-3'-methoxy-1,1'-biphenyl-4-yl)amino]nicotinic acid, which comprises the steps of:a) providing 3,5-difluoro-3'-methoxybiphenyl-4-amine, b) preparing and isolating an aminium salt of the 3,5-difluoro-3'-methoxybiphenyl-4-amine, and c) further reacting the aminium salt of 3,5-difluoro-3'-methoxybiphenyl-4-amine obtained in b) to obtain 2-[(3,5-difluoro-3'-methoxy-1,1'-biphenyl-4-yl)amino]nicotic acid.
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