102113-98-4Relevant articles and documents
Probing the Influence of PAd-DalPhos Ancillary Ligand Structure on Nickel-Catalyzed Ammonia Cross-Coupling
Lavoie, Christopher M.,Tassone, Joseph P.,Ferguson, Michael J.,Zhou, Yuqiao,Johnson, Erin R.,Stradiotto, Mark
, p. 4015 - 4023 (2018)
We report herein on the results of our combined experimental/computational study regarding the catalytic performance of PAd-DalPhos (L1) in nickel-catalyzed ammonia arylation for primary aniline synthesis. Primary arylamine C-N reductive eliminations occurring from arylnickel(II) parent amido complexes of the type (L)Ni(Ph)(NH2) were modeled by use of density-functional theory (DFT) methods, for a series of L1 derivatives. The dual aims were to assess the effect of structural modifications to L1 on potentially rate-limiting C-N reductive elimination and to identify promising candidates for experimental inquiry. Increasing the steric demand of the Paryl groups from o-tolyl (in L1) to mesityl (in L16) resulted in a significant lowering of the barrier to C-N reductive elimination (ΔG?RE), which can be attributed in part to interactions between the ligand Paryl groups and the nickel-bound amido ligand, as observed in noncovalent interaction (NCI) plots of the reductive elimination transition-state structures. Despite the favorability of L16 predicted on the basis of computational analysis focusing on C-N reductive elimination, this ancillary ligand performed poorly in experimental testing versus L1, suggesting that in practice the significant steric demands of L16 may discourage the formation of key catalytic intermediates. Modifications to the steric profile of the Paryl groups in L1 led to dramatic changes in catalytic performance, with the presence of an o-methyl proving to be important, among the L1 variants tested, in achieving useful catalytic performance in the Ni-catalyzed monoarylation of ammonia.
Effect of arylamino-carbazole containing hole transport materials on the device performance and lifetime of OLED
Joung, Kuk Soung,Kim, Kyu Sung,Kim, Seung Uk,Tak, So Hyun,Yu, Jae-Woong
, (2021/11/16)
We synthesized four hyper-conjugated aromatic hole transporting materials with different molecular geometry and energy levels by attaching arylamino moiety attached to the carbazole core. A brominated carbazole moiety reacted with an arylamino moiety using a Buchwald-Hartwig reaction. The characteristics of these hole transporting materials were investigated using TGA, DSC, UV–Vis and luminescence spectroscopy. The energy levels of all materials used in this study were estimated from cyclic voltammograms and absorption spectra. The hole transporting properties of the synthesized molecules were measured using single-carrier devices. All four hole transporting materials showed similar hole mobility. The effectiveness of hole transporting materials was compared by fabricating green-emitting organic light emitting diode (OLED) devices. It turned out that the device performances were critically dependent on the relative energy levels of the hole transporting layer and emission layer. However, the molecular geometry greatly influenced the device lifetime, determining thermally induced crystallization by the heat produced during device operation.
CH Activation of Cationic Bismuth Amides: Heteroaromaticity, Derivatization, and Lewis Acidity
Oberdorf, Kai,Grenzer, Patrick,Wieprecht, Nele,Ramler, Jacqueline,Hanft, Anna,Rempel, Anna,Stoy, Andreas,Radacki, Krzysztof,Lichtenberg, Crispin
, p. 19086 - 19097 (2021/12/09)
Cationization of Bi(NPh2)3 has recently been reported to allow access to single- and double-CH activation reactions, followed by selective transformation of Bi–C into C–X functional groups (X = electrophile). Here we show that this approach can successfully be transferred to a range of bismuth amides with two aryl groups at the nitrogen, Bi(NRaryl2)3. Exchange of one nitrogen-bound aryl group for an alkyl substituent gave the first example of a homoleptic bismuth amide with a mixed aryl/alkyl substitution pattern at the nitrogen, Bi(NPhiPr)3. This compound is susceptible to selective N–N radical coupling in its neutral form and also undergoes selective CH activation when transformed into a cationic species. The second CH activation is blocked due to the absence of a second aryl moiety at nitrogen. The Lewis acidity of neutral bismuth amides is compared with that of cationic species “[Bi(aryl)(amide)(L)n]+” and “[Bi(aryl)2(L)n]+” based on the (modified) Gutmann–Beckett method (L = tetrahydrofuran or pyridine). The heteroaromatic character of [Bi(C6H3R)2NH(triflate)] compounds, which are iso-valence-electronic with anthracene, is investigated by theoretical methods. Analytical methods used in this work include nuclear magnetic resonance spectroscopy, single-crystal X-ray diffraction, mass spectrometry, and density functional theory calculations.