Fuertes, Sara Chueca, Andrés J. Arnal, Lorenzo Martín, Antonio Giovanella, Umberto Botta, Chiara Sicilia, Violeta Heteroleptic Cycloplatinated N‑Heterocyclic Carbene Complexes: A New Approach to Highly Efficient Blue-Light Emitters New heteroleptic compounds of platinum­(II)-containing cyclometalated N-heterocyclic carbenes, [PtCl­(R-C^C*)­(PPh<sub>3</sub>)] [R-CH^C*-κC* = 3-methyl-1-(naphthalen-2-yl)-1<i>H</i>-imidazol-2-ylidene (R-C = Naph; <b>1A</b>), 1-[4-(ethoxycarbonyl)­phenyl]-3-methyl-1<i>H</i>-imidazol-2-ylidene (R = CO<sub>2</sub>Et; <b>1B</b>), and [Pt­(R-C^C*)­(py)­(PPh<sub>3</sub>)]­PF<sub>6</sub> (py = pyridine; R-C = Naph, <b>2A</b>; R = CO<sub>2</sub>Et, <b>2B</b>], have been prepared and fully characterized. All of them were obtained as the <i>trans</i>-(C*,PPh<sub>3</sub>) isomer in high yields. The selectivity of their synthesis has been explained in terms of the degree of transphobia (T) of pairs of ligands in trans positions. X-ray diffraction studies on both <b>2A</b> and <b>2B</b> revealed that only in <b>2A</b>, containing a C^C* with a more extended π system, do the molecules assemble themselves into head-to-tail pairs through intermolecular π···π contacts. The photophysical properties of <b>2A</b> and <b>2B</b> and those of the related compounds [Pt­(NC-C^C*)­(PPh<sub>3</sub>)­L]­PF<sub>6</sub> [NC-CH^C*-κC* = 1-(4-cyanophenyl)-3-methyl-1<i>H</i>-imidazol-2-ylidene; L = pyridine (py; <b>2C</b>), 2,6-dimethylphenylisocyanide (CNXyl; <b>3C</b>), and 2-mercapto-1-methylimidazole (MMI; <b>4C</b>)] have been examined to analyze the influence of the R substituent on R-C^C* (R-C = Naph; R = CO<sub>2</sub>Et, CN) and that of the ancillary ligands (L) on them. Experimental data and time-dependent density functional theory calculations showed the similarity of the electronic features associated with R-C^C* (R = CN, CO<sub>2</sub>Et) and their difference with respect to R-C^C* (R-C = Naph). All of the compounds are very efficient blue emitters in poly­(methyl methacrylate) films under an argon atmosphere, with QY values ranging from 68% (<b>2B</b>) to 93% (<b>2C</b>). In the solid state, the color of the emission changes to yellowish-orange for compounds <b>2A</b> (λ<sub>max</sub> = 600 nm) and <b>3C</b> (λ<sub>max</sub> = 590 nm) because of the formation of aggregates through intermolecular π···π interactions. <b>2C</b> and <b>3C</b> were chosen to fabricate fully solution-processed electroluminescent devices with blue-light (<b>2C</b>), yellow-orange-light (<b>3C</b>), and white-light (mixtures of <b>2C</b> and <b>3C</b>) emission from neat films of the compounds as emitting layers. NC-CH;imidazol -2-ylidene L;X-ray diffraction studies;2 B;solution-processed electroluminescent devices;Naph;PF;Efficient Blue-Light Emitters New heteroleptic compounds;2 C;3 C;MMI;R-CH;2- mercapto -1-methylimidazole;CO 2 Et;R-C;CN;QY;imidazol -2-ylidene 2017-04-07
    https://acs.figshare.com/articles/dataset/Heteroleptic_Cycloplatinated_N_Heterocyclic_Carbene_Complexes_A_New_Approach_to_Highly_Efficient_Blue-Light_Emitters/4829209
10.1021/acs.inorgchem.6b02826.s002