50777-76-9Relevant articles and documents
Synthesis and characterization of new PNNP-type chiral ligands
Tezcan, Burcu,Güzel, Bilgehan
, p. 315 - 316 (2018/12/11)
Polydentate ligands having both soft and hard centers are very effective ligands for the preparation of transition metal complexes. PNNP-type tetradentate diaminodiphosphine ligands are most preferred ligand types cause of their good efficiency for the asymmetric reactions. In this study, three different iminophosphine derivative PNNP-type chiral ligands were synthesized using (R)-(+)-1,1′-Binaphthyl-2,2′-diamine (R-BINAM) and d?phenylphosph?no benzaldehyde derivatives.
Dual encapsulation of electron transporting materials to simplify high-efficiency blue thermally activated delayed fluorescence devices
Kan, Wenjing,Duan, Chunbo,Sun, Mingzhi,Han, Chunmiao,Xu, Hui
, p. 7145 - 7157 (2016/10/22)
The charge flux balance and interfacial optimization are two core concerns when simplifying blue thermally activated delayed fluorescence (TADF) diodes, which reflects the more stringent demand on carrier transporting materials (CTM) as the embodiment of the contradiction between charge transportation and quenching suppression with the opposite requirement on intermolecular interactions. Herein, phenylbenzimidazole (PBI) was used as the core substituted with two diphenylphosphine oxide (DPPO) groups to form six dual-encapsulated charge-exciton separation (CES)-type electron transporting materials (ETM) with the collective name of xyPBIDPO. Through tuning the substitution positions of DPPO group, its two functions of resonance and steric effects were integrated and optimized to enhance charged moiety encapsulation without cost of reducing electroactivity. As the result, among xyPBIDPO, mmPBIDPO successfully realizes the balance of favorable electrical performance and interfacial interaction suppressions in virtue of its doubled mesa-substitution structure and roughly symmetrical configuration, rendering the good electron affinity of 2.8 eV, the high electron mobility by the level of 10-6 cm2 V-1 s-1 and effective PBI-core encapsulation. Consequently, mmPBIDPO was used to extremely simplify the blue TADF devices with the state-of-the-art performance from trilayer and quadruple-layer configurations, such as the maximum external quantum efficiency (EQE) beyond 20% and improved efficiency stability. This work not only established a solid example of CES-type ETM for high-performance simple structured blue TADF devices but also provided the direction of developing this kind of materials in the future.
Ruthenium(II) complexes containing a phosphine-functionalized thiosemicarbazone ligand: Synthesis, structures and catalytic C-N bond formation reactions via N-alkylation
Ramachandran, Rangasamy,Prakash, Govindan,Selvamurugan, Sellappan,Viswanathamurthi, Periasamy,Malecki, Jan Grzegorz,Linert, Wolfgang,Gusev, Alexey
, p. 11405 - 11422 (2015/03/05)
A series of ruthenium(II) complexes incorporating a thiosemicarbazone chelate tethered with a diphenylphosphine pendant have been studied. Thus, [(PNS-Et)RuCl(CO)(PPh3)] (1), [N,S-(PNS-Et)RuH(CO)(PPh3)2] (2) and [(PNS-Et)RuCl(PPh3)] (3) were synthesized by reactions of various RuII precursors with 2-(2-(diphenylphosphino)benzylidene)-N-ethylthiosemicarbazone (PNS-Et). However, complexation of PNS-Et with an equimolar amount of [RuCl2(dmso)4] resulted in two different entities [(PNS-Et)RuCl(dmso)2] (4) and [(PNS-Et)2Ru] (5) with different structural features in a single reaction. All the RuII complexes have been characterized by analytical and various spectroscopic techniques. Compounds 1-5 were recrystallized, and the X-ray crystal structures have been reported for 1, 2 and 5. In the complexes 1 and 3-5 the ligand coordinated in a tridentate monobasic fashion by forming PNS five- and six-membered rings, whereas in 2, the ligand coordinated in a bidentate monobasic fashion by forming a strained NS four-membered ring. Furthermore, compounds 1-5 showed catalytic activity in N-alkylation of heteroaromatic amines. Notably, complexes 1-3 were found to be very efficient catalysts toward N-alkylation of a wide range of heterocyclic amines with alcohols. In the presence of a catalytic amount of 2 with 50 mol% of KOH, N1,C5-dialkylation of 4-phenylthiazol-2-amine has been investigated. Reaction of in situ generated aldehyde with amine yields the N1,C5-dialkylated products through the hydride ion transformation from alcohol. Complexes 1-3 also catalyzed a variety of coupling reactions of benzyl alcohols and sulfonamides, which were realized often with 99% isolated yields. Advantageously, only one equivalent of the primary alcohol was consumed in the process.
