Syntheses and structures of two [Au(I)PPh3]-complexes with 2-aceneoxazolethiolates as ligands.

The crystal structures of two thiolato complexes of the type [Au(SR)(PPh3)] with SR=2-mercaptobenzoxazol-2-yl (MBOx) and SR=2-mercaptoanthraceneoxazol-2-yl (MAOx) were determined from X-ray powder diffraction data. Both complexes include η1-S-monodentate ligands with the nitrogen atom preferably oriented towards the gold atom. [Au(MBOx)(PPh3)] ( 1a) represents a new triclinic polymorph of [Au(MBOx)(PPh3)], whereas [Au(MAOx)(PPh3)] ( 2) is hitherto unknown and yields information about the molecular structure of the ligand MAOx as well as the coordination geometry in 2. The structure determinations were validated by low temperature XRPD measurements. DTA-TG and in-situ XRPD measurements revealed a monotropic phase transition of 1a at 443 K to a monoclinic phase. Additionally, solid-state DFT-D calculations using CASTEP were carried out to evaluate the experimental results. [ABSTRACT FROM AUTHOR]