Abstract

Almost all Iridium(III) complexes employed both as dopants in PhOLEDs and as pharmaceuticals and fluorescence bioprobes are racemic mixtures. In this study the single enantiomers of the most stable diastereomeric form fac-trans-N-N, bis[2-(4,6-difluorophenyl)pyridinato-C(2),N](picolinato)iridium(III) (FIrpic) were separated and analysed. The data obtained showed that the complex can be separated into stable optically active Λ and Δ isomers employing cellulose based chiral stationary phase both in normal and polar phase mode. Their chirality was confirmed and their absolute configuration assigned employing several methods (DFT and TDDFT calculations, CD and VCD). The CPL spectroscopy of the isolated enantiomers of FIrpic was also recorded due to its possible value in the OLEDs field. The chromatographic method was applied for a semipreparative purpose demonstrating that polar organic solvent chromatography (POSC) could be used to avoid the low-solubility issues associated with these Iridium(III) complexes. Finally, the chemical and stereochemical stability of the single isomers was evaluated under thermal stress by liquid chromatography coupled to high-resolution mass spectrometry (LC-QTOF) on both chiral and achiral columns. No racemization and/or isomerization was observed; however, the dissociation of the ancillary ligand was demonstrated employing LC-QTOF.

Autore Pugliese

• Gigli Giuseppe , Ciccarella Giuseppe

Tutti gli autori

• Citti C. , Battisti U.M. Ciccarella G. , Maiorano V. , Gigli G. , Abbate S. , Mazzeo G. , Castiglioni E. , Longhi G. , Cannazza G.

Titolo volume/Rivista

JOURNAL OF CHROMATOGRAPHY A

Anno di pubblicazione

2016

ISSN

1873-3778

ISBN

Non Disponibile

Numero di citazioni Wos

9

Ultimo Aggiornamento Citazioni

28/04/2018

Numero di citazioni Scopus

9

Ultimo Aggiornamento Citazioni

28/04/2018

Settori ERC

Non Disponibile

Codici ASJC

Non Disponibile