A thiophenic alkynylplatinum(II) terpyridyl complex: synthesis and photophysical properties

A new thiophenic alkynylplatinum(II) terpyridyl complex [tBuArC equivalent to CPt(tpy)]PF6 (tpy = 2,2 ':6 ',2 ''-terpyridine; Ar = [(MeC4H2S)(C equivalent to C)](2)C6H2) has been synthesized in five steps in 45% total yield. The photophysical properties were studied by steady-state spectroscopy and transient spectroscopy and obvious metal-metal interactions and pi-pi stacking were found in a series of solvents. Concentration dependent emission data show that the complex exhibited aggregation-induced fluorescence enhancement at low concentrations while aggregation-induced fluorescence quenching at high concentrations. The complex displayed biexponential decays with lifetimes in the range of nanoseconds in dilute dichloromethane and acetonitrile solutions.