Synthesis, structure and luminescent properties of rhenium(I) carbonyl complexes containing pyrimidine-functionalized N-heterocyclic carbenes

Synthesis, structures and photophysical properties of a series of neutral fac-[Re(CO)3(C^N)Cl] complexes, where C^N is a pyrimidine-functionalized N-heterocyclic carbene [3-methyl-1-(2-pyrimidine)imidazol-2-ylidene, 1; 3-n-butyl-1-(2-pyrimidine)imidazol-2-ylidene, 2; 3-benzyl-1-(2-pyrimidine)imidazol-2-ylidene, 3; 3-mesityl-1-(2-pyrimidine)-imidazol-2-ylidene, 4] are reported. These complexes have been characterized by 1H NMR, 13C NMR, elemental analysis, and IR spectra. Their electrochemical and photophysical behaviors, along with the X-ray crystal structures of 2 and 4, are also reported. In both degassed CH2Cl2 solutions and solid state at room temperature, complexes 1–4 exhibit the emissions at 515–570 nm.

Graphical abstractFour rhenium(I) carbonyl complexes containing pyrimidine-functionalized N-heterocyclic carbenes have been prepared and characterized by 1H NMR, 13C NMR, elemental analysis, and IR spectra. Their electrochemical and photophysical behaviors, along with the X-ray crystal structures of 2 and 4, are also reported. In both degassed CH2Cl2 solutions and solid state at room temperature, complexes 1–4 exhibit the emissions at 515–570 nm.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Four Re(I) carbonyl complexes containing N-heterocyclic carbenes were prepared. ► Two complexes were determined by X-ray diffraction analysis. ► Their electrochemical and photophysical behaviors were studied.