182227-72-1Relevant academic research and scientific papers
Efficient Intramolecular Charge-Transfer Fluorophores Based on Substituted Triphenylphosphine Donors
Deng, Chao,Jiang, Yongshi,Liu, Zhang,Su, Liwu,Tsuboi, Taiju,Wang, Dan,Zhang, Qisheng
, p. 15049 - 15053 (2021)
Triphenylphosphine (TPP)-based luminescent compounds are rarely investigated because of the low photoluminescence quantum yield (PLQY). Here, we demonstrate that introducing steric hindrance groups to the TPP moiety and separating the orbitals involved in the transition can drastically suppress the non-radiative decay induced by structural distortion of TPP in the excited state. High PLQY up to 0.89 as well as thermally activated delayed fluorescence are observed from the intramolecular charge-transfer (ICT) molecules with substituted TPP donors (sTPPs) in doped films. The red organic light-emitting diodes employing these emitters achieve comparable external quantum efficiencies to the control device containing a classical phosphorescent dye, revealing the great potential of the ICT emitters based on electrochemically stable sTPPs.
Synthesis of crowded triarylphosphines carrying functional sites
Sasaki, Shigeru,Murakami, Fumiki,Murakami, Midori,Watanabe, Mariko,Kato, Kiyotoshi,Sutoh, Katsuhide,Yoshifuji, Masaaki
, p. 2664 - 2672 (2007/10/03)
4,4′-Diphosphinobiaryls and 1,3- and 1,4-borylphosphinobenzenes carrying crowded triarylphosphine moieties were synthesized by reaction of the corresponding diarylchlorophosphine with an arylcopper(I) reagent. Intramolecular interaction of the phosphorus redox center with the other phosphorus or the boron redox center was investigated by cyclic voltammetry. 4,4′-Diphosphinobiaryls displayed two-step reversible redox waves with slight differences of the oxidation potentials due to weak interaction between two phosphorus redox centers across 4,4′-biarylene linkage. Borylphosphinobenzenes showed two step redox waves corresponding to oxidation at the phosphorus and reduction at the boron. Although significant interaction between the phosphorus and boron redox centers was not observed in the cyclic voltammograms due to large difference of the redox potentials between phosphorus and boron redox centers, an absorption due to weakly interacting phosphorus and boron was observed in the UV-Vis spectrum of the 1,4-borylphosphinobenzene.
Synthesis, Coordination Chemistry and Ligand Properties of Secondary Phosphines R(Ar*)PH with Bulky Aromatic Substituents - Molecular Structure of Ph(2,4,6-iPr3C6H2)PH, (2,4,6-iPr3C6H2)2PH and ClAu[PhP(2,4,6-tBu3C6H2)H]
Brauer, David J.,Bitterer, Frank,D?rrenbach, Frank,He?ler, Gisbert,Stelzer, Othmar,Krüger, Carl,Lutz, Frank
, p. 1183 - 1196 (2007/10/03)
The secondary phosphines R(Ar*)PH (R = Me, iPr, Ph, Mes, Ar*) (2a-2h) with bulky aromatic substituents Ar* (Ar* = 2,3,6-R′3C6H2, R′ = iPr, tBu) are obtained in good yields by reaction of RPCl2, PCl3, PBr3 or Ar*P(Cl,Br)2 with 2,4,6-tBu3C6H2Li or 2,4,6-iPr3C6H2MgBr and subsequent reduction of the intermediate halophosphines R(Ar*)PX (X = Cl, Br) with LiAlH4. The X-ray structural analysis of Ph(2,4,6-iPr3C6H2)PH (2g), space group P1, shows P-C-distances of 1.824(1) and 1.838(1)?. The lithium derivatives of 2a-2c are monomeric in solution as indicated by the 1 : 1 : 1 : 1-quartet 7Li-31P fine structure of the 31P{1H} NMR signals at low temperatures. 2a-2c and 2f-2h form Ni(0) and Fe(0) complexes (CO)3NiL (6a-6f) and Fe(CO)4L (7a-7d), respectively. The Tolman electronic parameters ν of the bulky ligands are almost identical. Within the series 2a-2h the spatial shielding of the P atoms has been estimated using advanced molecular modeling techniques. The bulky ligancl 2c forms coinage metal complexes [Cu(CH3CN)2(2c)2] [PF6] (8). Cu2Cl2(2c)2 (9) and Cl-Au(2c) (10). While 10 is monomeric in solution, in the solid state it forms pairs of head to tail oriented monomers with almost linear Cl-Au-P skeletons (Cl-Au-P 175.47(9)°) as shown by an X-ray structural analysis.
Influence of ortho Methyl and Isopropyl Substituents on the Reactivity of N-t-Butyl P-Arylphosphonamidic Chlorides with Isopropylamine and t-Butylamine: Steric Acceleration of Metaphosphonimidate Formation by an Elimination-Addition Mechanism; Contrasting Behaviour of N,N-Dimethyl P-A...
Freeman, Sally,Harger, Martin J.
, p. 1399 - 1406 (2007/10/02)
The two types of phosphonamidic chloride ArP(O)(Cl)NMe2, (5) and ArP(O)(Cl)NHBut (7) have been prepared with Ar=Ph, o-MeC6H4, 2,4,6-Me3C6H2, and 2,4,6-Pri3C6H2.Both types give the expected phosphonic diamide substitution products with PriNH2 and ButNH2 in MeCN, but the two types display contrasting reactivity.With ButNH2 the NMe2 substrates (5) become progressively less reactive as the degree of steric crowding increases, and although the decrease is quite small (70-fold overall) it seems consistent with an associative N2(P)> mechanism.These substrates react >=100 times faster with PriNH2, than with ButNH2 and in PriNH2-ButNH2 competitive experiments they give almost exclusively (>=99percent) the product derived from the less hindered PriNH2.For the NHBut substrates (7) with ButNH2, there is little difference in reactivity between the Ph and o-MeC6H4 compounds, and between the 2,4,6-Me3C6H2 and 2,4,6-Pri3C6H2 compounds, but remarkably the more crowded pair of substrates is the more reactive, by a factor of ca. 100.Also, in competitive experiments these substrates display relatively little preference for reaction with PriNH2.Here a dissociative elimination-addition mechanism, with a metaphosphonimidate intermediate, is seen to be important.A possible explanation of the steric acceleration is advanced.The ability of (7; Ar=Ph) to undergo substitution by elimination-addition makes possible the phosphonylation of unreactive nucleophiles such as ButOH and Pri2NH under mild conditions.
