Synthesis of chelating tertiary phosphine oxides via palladium-catalysed C-P bond formation

Bis(diphenylphosphine oxides) and bis(tert-butyl(phenyl)phosphine oxides) of 1,10-phenanthroline, 2,2'-bipyridine and pyridine were synthesised in good yields via the Pd(OAc)(2)/dppf mediated cross-coupling reactions between 6,6'-dichloro-2,2'-bipyridine, 2,9-dichloro-1,10-phenanthroline, or 2,6-dichloropyridine and the corresponding secondary phosphine oxides. These compounds represent potential tetradentate chelating ligands for ions of f-block elements. (C) 2017 Elsevier Ltd. All rights reserved.