Synthesis of multi-1,10-phenanthroline ligands with 1,3-phenylene linkers and their lithium complexes.

The synthesis of two multisite ligands containing four and five 1,10-phenanthroline (phen) chelates in line, respectively, is presented. The connectors are 1,3-phenylene linkers. The two ligands were prepared following multistep procedures, the two key reactions being the Suzuki coupling reaction between aromatic nuclei and the nucleophilic addition of aryllithium derivatives onto a phen fragment. The coordination chemistry of both ligands with Li+ ions was very clean and selective, whereas their reaction with copper(I) led to intractable mixtures of insoluble complexes. The tetraphen and the pentaphen compounds afforded almost quantitatively the four- and five-lithium double-stranded helical complexes, respectively. The helical systems are probably highly wound, as indicated by NMR measurements. The pronounced strain of the 5-Li+ complex is reflected by the easy loss of a lithium cation, as shown by electrospray mass spectrometry.

Références

Titre
Synthesis of multi-1,10-phenanthroline ligands with 1,3-phenylene linkers and their lithium complexes.
Type de publication
Article de revue
Année de publication
2005
Revue
Chem. Eur. J.
Volume
11
Pagination
4374–4386
Date de publication
jul
ISSN
0947-6539
Soumis le 17 avril 2018