Synthesis of new pyrrole–pyridine-based ligands using an in situ Suzuki coupling method

• Matthias Böttger,
• Björn Wiegmann,
• Steffen Schaumburg,
• Peter G. Jones,
• Wolfgang Kowalsky and
• Hans-Hermann Johannes

Beilstein J. Org. Chem. 2012, 8, 1037–1047, doi:10.3762/bjoc.8.116

• ; in situ generation; pyrrole-pyridine; Suzuki coupling; Introduction Tridentate ligands have recently received attention in the area of rare-earth-metal complex chemistry [1][2][3][4][5]. Many rare-earth-metal cations, such as europium(III), have the tendency to be nine-coordinating species. Besides

• of chemistry. The pyrrole–pyridine structural motif is featured in current studies, owing to its complexation properties towards first-row transition metals (Fe, Co, Ni, Cu, Zn) [18] and ruthenium [19]. The intramolecular proton transfer of these species is also of interest for vibrational

• homoleptic complexes of europium(III) (right). Pyrrole–pyridine-based structures synthesized in this study. Retrosynthetic approach for structures 1–3. Synthesis of the heteroaryl bromides used in the coupling reaction. Generation of the borate intermediate 21/22. In situ Suzuki coupling reactions of the