Kinetics and photophysical behavior of the P,N-ReI complex [P,N-{(C6H5)2(C5H4N)P}Re(CO)3(O-O3SCF3)]: A directly coordinated (and labile) triflate

© 2017 Elsevier Ltd The reaction of [P,N-{(C6H5)2(C5H4N)P}Re(CO)3Br] (RePNBr) with silver triflate leads to the complex [P,N-{(C6H5)2(C5H4N)P}Re(CO)3(O-CF3SO3)] (RePNTfO) with moderate yield. This new P,N-ReI triflate compound contains the anion directly coordinated to the metal, completing an octahedral environment. RePNTfO displays in dichloromethane (DCM) solution an irreversible oxidation about +1.35 V and three irreversible reduction processes at −1.38 V, −2.03 V and −2.30 V. Oxidation has been attributed to the ReI/ReII couple, while the reduction corresponds to PN-ligand processes, which is consistent with those computed by means of DFT. The absorption spectrum of RePNTfO in DCM displays a maximum at 295 nm (ε = 7.1 × 103 M−1 cm−1) and a shoulder around 350 nm (ε = 1.8 × 103 M−1 cm−1), which have been assigned to intraligand (π → π∗) and metal to ligand charge transfer (MLCT, dπ → π∗) transitions with the help of DFT/TDDFT. Excitation of RePNTfO in DCM at 350 nm leads to an emi