N-aryl heterocycles via coupling reactions with arylboronic acids

Compounds having a partial 2-pyridone structure or 3-pyridazinones can be s electively N-arylated with phenylboronic acids according to the procedure d escribed by Chan and Lam. This procedure leads to N5-arylated imidazo[4,5-c ]pyridin-4-ones, precursors of potent factor Xa inhibitors. In addition, th e synthesis of N-aryl substituted pyrrole- and indole-2-carboxylic acid est ers is described In the indole series this procedure offers a flexible entr y in the synthesis of different 1,3-diaryl-2-carboxyindoles. (C) 1999 Elsev ier Science Ltd. Ail rights reserved.