Mixed Cu(I)/Au(I) coordination polymers as reversible turn-on vapoluminescent sensors for volatile thioethers

Vapour-phase thioethers play an important role in a wide number of fields, including plant biology, chemical weapon disposal, and brewing but few sensor materials are known. The emissive coordination polymer Cu1/2Au1/2CN does not react with vapour phase dimethyl sulphide (DMS) or diethyl sulphide (DES) despite the independent synthesis of emissive [Cu1/2Au1/2CN](2)(DMS) and [Cu1/2Au1/2CN](2)(DES) from their constituent components in solution. However, the doped Cu2/3Au1/3CN rapidly reacts in the solid state with both of these vapour phase thioethers reversibly, with a change in emission from 380/560 nm to 460 nm (DMS) or 420 nm (DES), illustrating that doping the inactive parent Cu1/2Au1/2CN with Cu(I) generates an active sensor material. This response can be thermally cycled with little to no loss in functionality. [Cu1/2Au1/2CN](2)(DMS), [Cu2/3Au1/3CN](2)(DMS), and [Cu2/3Au1/3CN](2)(DES) were structurally characterized as 3-D network structures supported by aurophilic interactions.