title: Solvent-assisted spontaneous resolution of a 16-membered ring containing gold(I) showing short Au...Au aurophilic interaction and a figure-eight conformation.
abstract: The achiral 4,6-bis(diphenylphosphino) phenoxazine (nixantphos) ligand was used to synthesize a gold(I) complex, [Au2(nixantphos)2](NO3)2, containing a 16-membered [Au2(nixantphos)2](+2) cationic ring in a chiral figure-eight conformation. The single crystal X-ray diffraction analysis of [Au2(nixantphos)2](NO3)2.3MeOH.H2O (1) and [Au2(nixantphos)2](NO3)2.4MeCN (2) revealed a solvent-assisted spontaneous resolution of the [Au2(nixantphos)2](NO3)2 complex. By changing the nature of the solvent, homochiral hydrogen bonded helices (1) and heterochiral hydrogen bonded monomers (2) were obtained. Multinuclear NMR spectroscopy showed the evidence of chemical exchange phenomenon related to the interconversion of the enantiomeric skeletons of the 16-membered macrocycle in solution. The existence of the Au...Au aurophilic interaction was confirmed by the analysis of the spin-system in the (31)P NMR spectrum.
authors.affiliation: Institute of Structural Chemistry, Chemical Research Center, Hungarian Academy of Sciences, PO Box 17, H-1525, Budapest, Hungary.
authors.forename: Tünde
authors.initials: T
authors.lastname: Tunyogi
authors.forename: Andrea
authors.initials: A
authors.lastname: Deák
authors.forename: Gábor
authors.initials: G
authors.lastname: Tárkányi
authors.forename: Péter
authors.initials: P
authors.lastname: Király
authors.forename: Gábor
authors.initials: G
authors.lastname: Pálinkás