Abstract
The crystal structures for cis-(Ph2PCH=CHPPh2)(AuI)2 and trans-(Ph2PCH=CHPPh2)(AuI)2 are reported. The structure of cis-(Ph2PCH=CHPPh2)(AuI)2 reveals a short intramolecular Au–Au distance of 2.9526(5) Å, while the structure of trans-(Ph2PCH=CHPPh2)(AuI)2 shows intermolecular Au–Au distances of 3.2292(7) Å. Structural data for the iodide complexes are compared to previously reported crystal structural data for cis- and trans-(Ph2PCH=CHPPh2)(AuCl)2 and dppbz(AuCl)2. The quantum yields for the photochemical isomerization of cis-(Ph2PCH=CHPPh2)(AuX)2 with 334-nm light, Φ(cis → trans), are 0.204, 0.269, and 0.363 for X = Cl, Br, and I, respectively. Prior results from ab initio calculations on the model cis- and trans-Au2X2C2H2(PH2)2 complexes aid in the interpretation of the correlation between the quantum yield for isomerization and the calculated aurophilic attraction potential V(Re).