Tuning aurophilic interactions in dinuclear phosphinegold(i) thiolates containing hydrogen bonding functionalities

A common feature of the solid state structures of [(AuSC₆H ₄{C(O)Y}-2)₂(μ-dppf)], where dppf is bis(diphenylphosphine)ferrocene, and Y = OH (1), NH₂ (2) and N(H)Me (3) is the formation of a chain motif. Association between the molecules is found to be highly dependent on the nature of Y so that in 1 only hydrogen bonding between molecules is observed. In 2, both hydrogen bonding and aurophilic interactions are found. By contrast, in 3 only aurophilic interactions contribute to the formation of the chain. These results are consistent with a similar energy of stabilisation and structure-directing propensity for the hydrogen bonding and aurophilic association operating in these systems.