Diimine ligand structure effects on photophysical properties of tricarbonyl rhenium(I) complexes having arylborane charge transfer units

We report the synthesis and photophysical properties of a novel tricarbonyl rhenium(I) complex having a (dimesityl)boryldurylethynyl (DBDE) group at the 4-position of a 2,2′-bipyridine (bpy) ligand, fac -[Re(CO) 3 (DBDE-bpy)Br] = ReBbpy , and discuss the diimine ligand structure effects on the spectroscopic and photophysical properties of the complex by comparing with those of the relevant 4-DBDE-1,10-phenanthroline (phen) type complex: fac -[Re(CO) 3 (DBDE-phen)Br] = ReBphen . The present study demonstrated that ReBbpy showed smaller DBDE effects on the spectroscopic and photophysical properties compared with ReBphen , whose origin was discussed in terms of the redox, absorption/emission, and time-dependent density functional theory calculation data on the complexes.