2024-03-28T18:12:25Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/1562952019-06-26T07:20:15Zcom_10261_52707com_10261_5col_10261_52708
00925njm 22002777a 4500
dc
Carmona, María
author
Rodríguez, Ricardo
author
Méndez, Isabel
author
Passarelli, Vincenzo
author
Lahoz, Fernando J.
author
García-Orduña, P.
author
Carmona, Daniel
author
2017
Ligands LH1–LH3 have been prepared by two successive condensation/reduction steps. These ligands react with MCl3 (M = Rh, Ir) rendering the trichlorido complexes [MCl3(κ3N,N’,P-LH)] (M = Rh, LH = LH1 (1), LH2 (2), LH3 (3); M = Ir, LH = LH1, (4)) as racemic mixtures of fac and mer isomers. Only one of the two possible fac isomers was detected. The mer isomer of the rhodium compounds 1–3 quantitatively isomerizes to the more stable fac isomer, whereas the mer isomer of the iridium complex 4 does not. DFT calculations indicate a dissociative pathway for this isomerization. In the presence of acetate or trifluoroacetate, complexes 1–3 or 4, respectively, undergo cyclometallation of their free benzylic arm affording the corresponding dichlorido compounds [MCl2(κ4C,N,N’,P-L)] (M = Rh, L = L1 (5), L2 (6), L3 (7); M = Ir, L = L1 (8)). Only one of the three possible enantiomeric pairs of coordination isomers was detected. The configuration at the stereogenic centres, namely the metal and the iminic nitrogen atom is stereospecifically predetermined. DFT calculations reveal that the cyclometallation follows an acetateassisted mechanism and indicate that the isolated isomers are the most stable. Complexes 1–8 have been characterized by analytical and spectroscopic means and by the determination of the crystal structures of the complexes 1, 3 and 5–8 by X-ray diffractometry.
Dalton Transactions 46(22): 7332-7350 (2017)
1477-9226
http://hdl.handle.net/10261/156295
1477-9234
http://dx.doi.org/10.13039/501100003339
http://dx.doi.org/10.13039/501100000780
http://dx.doi.org/10.13039/501100003329
http://dx.doi.org/10.13039/501100010067
Stereospecific control of the metal-centred chirality of rhodium(III) and iridium(III) complexes bearing tetradentate CNN′P ligands