2622-60-8Relevant articles and documents
Osmium(II)-bis(dihydrogen) complexes containing C aryl, C NHC-chelate ligands: Preparation, bonding situation, and acidity
Bolao, Tamara,Esteruelas, Miguel A.,Fernndez, Israel,Oate, Enrique,Palacios, Adrin,Tsai, Jui-Yi,Xia, Chuanjun
, p. 778 - 789 (2015)
The hexahydride complex OsH6(PiPr3)2 (1) reacts with the BF4-salts of 1-phenyl-3-methyl-1-H-benzimidazolium, 1-phenyl-3-methyl-1-H-5,6-dimethyl-benzimidazolium, and 1-phenyl-3-methyl-1-H-imidazolium t
Heteroleptic platinum(ii) NHC complexes with a ?C? cyclometalated ligand-synthesis, structure and photophysics
Tronnier, Alexander,Heinemeyer, Ute,Metz, Stefan,Wagenblast, Gerhard,Muenster, Ingo,Strassner, Thomas
, p. 1680 - 1693 (2015)
Platinum(ii) complexes [(NHC)Pt(L)] with various β-diketonate based auxiliary ligands (L: 3-meacac = 3-methylacetylacetonato, dpm = dipivaloylmethanato, dbm = dibenzoylmethanato, mesacac = dimesitoylmethanato, duratron = bis(2,3,5,6-tetramethylbenzoyl)methanato) and a ?C? cyclometalated N-heterocyclic carbene ligand (NHC: dpbic = 1,3-diphenylbenzo[d]imidazol-2-ylidene, dpnac = 1,3-diphenylnaphtho[2,3-d]imidazol-2-ylidene or bnbic = 1-phenyl-3-benzylbenzo[d]imidazol-2-ylidene) were found to show different aggregation and photophysical properties depending on the auxiliary ligand. Eight complexes were prepared from a silver(i)-NHC intermediate by transmetalation, cyclometalation and subsequent treatment with potassium-tert-butanolate and β-diketone. They were fully characterized by standard techniques including 195Pt NMR. Five complexes were additionally characterized by 2D NMR spectroscopy (COSY, HSQC, HMBC and NOESY). Solid-state structures of five complexes could be obtained and show the tendency of the square-planar compounds to form pairs with different Pt-Pt distances depending on the bulkiness of the substituents at the auxiliary ligand. The result of the photophysical measurements in amorphous PMMA films reveals quantum yields of up to 85% with an emission maximum in the blue region and comparatively short decay lifetimes (3.6 μs). Density functional theory (DFT/TD-DFT) calculations were performed to elucidate the emission process and revealed a predominant 3ILCT/3MLCT character. Organic light-emitting devices (OLEDs) comprising one of the complexes achieved 12.6% EQE, 11.9 lm W-1 luminous efficacy and 25.2 cd A-1 current efficiency with a blue emission maximum at 300 cd m-2. The influence of an additional hole-transporter in the emissive layer was investigated and found to improve the device lifetime by a factor of seven.
Twist it! the acid-dependent isomerization of homoleptic carbenic iridium(III) complexes
Osiak, Jaroslaw G.,Setzer, Tobias,Jones, Peter G.,Lennartz, Christian,Dreuw, Andreas,Kowalsky, Wolfgang,Johannes, Hans-Hermann
, p. 3295 - 3298 (2017)
The first successful meridional to facial isomerization of homoleptic carbenic iridium(iii) complexes is presented. The Br?nsted-acid-mediated procedure allows the conversion of large amounts of material and additionally provides an in situ purification b
Methanol as the C1source: Redox coupling of nitrobenzenes and alcohols for the synthesis of benzimidazoles
An, Jie,Lai, Zemin,Li, Hengzhao,Peng, Mengqi,Sun, Yanhao,Yan, Zihan,Yang, Ruoyan,Zhang, Yuntong
supporting information, p. 748 - 753 (2022/02/02)
We present an operationally simple redox coupling for the synthesis of N-1 substituted benzimidazoles using feedstock building block 2-nitroaniline derivatives as the precursors and methanol as the C1 source. Higher atom, step, and redox economies and exc
Copper nanoparticle anchored biguanidine-modified Zr-UiO-66 MOFs: a competent heterogeneous and reusable nanocatalyst in Buchwald-Hartwig and Ullmann type coupling reactions
Veisi, Hojat,Neyestani, Narges,Pirhayati, Mozhgan,Ahany Kamangar, Sheida,Lotfi, Shahram,Tamoradi, Taiebeh,Karmakar, Bikash
, p. 22278 - 22286 (2021/07/02)
We have designed a functionalized metal-organic framework (MOF) of UiO topology as a support, with an extremely high surface area, adjustable pore sizes and stable crystalline coordination polymeric structure and implanted copper (Cu) nanoparticles thereon. The core three dimensional Zr-derived MOF (UiO-66-NH2) was modified with a biguanidine moiety following a covalent post-functionalization approach. The morphological and physicochemical features of the material were determined using analytical methods such as FT-IR, SEM, TEM, EDX, atomic mapping, XRD and ICP-OES. The SEM and XRD results justified the unaffected morphology of Zr-MOF after structural modifications. The as-synthesized UiO-66-biguanidine/Cu nanocomposite was catalytically explored in the aryl and heteroaryl Buchwald-Hartwig C-N and Ullmann type C-O cross coupling reactions with excellent yields. A library of biaryl amine and biaryl ethers was synthesized over the catalyst under mild and green conditions. Furthermore, the catalyst was isolated by centrifugation and recycled 11 times with no significant copper leaching or change in its activity.
