- Early transition metal compound and preparation method and intermediate thereof and application of early transition metal compound in polymerization of olefin
-
The invention relates to the field of catalysts for olefin polymerization, in particular to an early transition metal compound and a preparation method and intermediate thereof and application of theearly transition metal compound in polymerization of olefin. The early transition metal compound is a compound represented by a formula (1). When the early transition metal compound or crystal of theearly transition metal compound is applied to catalysis of olefin, high catalytic activity is achieved, and excellent catalytic activity is achieved in a wide range of polymerization conditions; and the catalyst has low cost, and is favorable for industrial production.
- -
-
Paragraph 0294; 0296; 0298; 0299
(2019/11/13)
-
- Electrophilic Phosphonium Cation-Mediated Phosphane Oxide Reduction Using Oxalyl Chloride and Hydrogen
-
The metal-free reduction of phosphane oxides with molecular hydrogen (H2) using oxalyl chloride as activating agent was achieved. Quantum-mechanical investigations support the heterolytic splitting of H2 by the in situ formed electrophilic phosphonium cation (EPC) and phosphane oxide and subsequent barrierless conversion to the phosphane and HCl. The reaction can also be catalyzed by the frustrated Lewis pair (FLP) consisting of B(2,6-F2C6H3)3 and 2,6-lutidine or phosphane oxide as Lewis base. This novel reduction was demonstrated for triaryl and diaryl phosphane oxides providing access to phosphanes in good to excellent yields (51–93 %).
- Stepen, Arne J.,Bursch, Markus,Grimme, Stefan,Stephan, Douglas W.,Paradies, Jan
-
supporting information
p. 15253 - 15256
(2018/10/24)
-
- Convergent modulation of singlet and triplet excited states of phosphine-oxide hosts through the management of molecular structure and functional-group linkages for low-voltage-driven electrophosphorescence
-
The controllable tuning of the excited states in a series of phosphine-oxide hosts (DPExPOCzn) was realized through introducing carbazolyl and diphenylphosphine-oxide (DPPO) moieties to adjust the frontier molecular orbitals, molecular rigidity, and the location of the triplet excited states by suppressing the intramolecular interplay of the combined multi-insulating and meso linkage. On increasing the number of substituents, simultaneous lowering of the first singlet energy levels (S1) and raising of the first triplet energy levels (T1, about 3.0 eV) were achieved. The former change was mainly due to the contribution of the carbazolyl group to the HOMOs and the extended conjugation. The latter change was due to an enhanced molecular rigidity and the shift of the T1 states from the diphenylether group to the carbazolyl moieties. This kind of convergent modulation of excited states not only facilitates the exothermic energy transfer to the dopants in phosphorescent organic light-emitting diodes (PHOLEDs), but also realizes the fine-tuning of electrical properties to achieve the balanced carrier injection and transportation in the emitting layers. As the result, the favorable performance of blue-light-emitting PHOLEDs was demonstrated, including much-lower driving voltages of 2.6 V for onset and 3.0 V at 100 cd m -2, as well as a remarkably improved E.Q.E. of 12.6 %.
- Han, Chunmiao,Zhang, Zhensong,Xu, Hui,Xie, Guohua,Li, Jing,Zhao, Yi,Deng, Zhaopeng,Liu, Shiyong,Yan, Pengfei
-
p. 141 - 154
(2013/03/13)
-
- Allyl acetate hydroformylation process
-
A process for the production of 4-acetoxybutyraldehyde is described. The process comprises reacting allyl acetate with a mixture of carbon monoxide and hydrogen in the presence of a solvent and a catalyst comprising a rhodium complex and a diphosphine. The diphoshine is a substituted or unsubstituted 2,2′-bis(dihydrocarbylphosphino)diphenyl ether. The process gives a high ratio of 4-acetoxybutyraldehyde:3-acetoxy-2-methylpropionaldehyde.
- -
-
Page/Page column 3
(2011/06/19)
-
- A PROCESS FOR THE REDUCTION OF A TERTIARY PHOSPHINE OXIDE TO THE CORRESPONDING TERTIARY PHOSPHINE IN THE PRESENCE OF A CATALYST AND USE OF A TERTIARY PHOSPHINE FOR REDUCING A TERTIARY PHOSPHINE OXIDE IN THE PRESENCE OF A CATALYST
-
A process for the conversion of a tertiary phosphine oxide to the corresponding tertiary phosphine comprising reacting said tertiary phosphine oxide with a reducing tertiary phosphine, in the presence of a catalyst that catalyzes the conversion.
- -
-
Page/Page column 22-23
(2011/10/13)
-
- Niew bidentate diphosphine ligands on the basis of diphenyl ether
-
A new procedure has been developed for the preparation of new bidentane diphosphine ligands, 2,2′-diphosphinodiphenyl ethers containing various substituents on the phosphorus, which differ in both electron-donor and steric parameters.
- Veits,Mutsenek,Neganova,Beletskaya
-
p. 1583 - 1586
(2007/10/03)
-
- Organolithium displacement of aryl anions from tertiary phosphine derivatives of diphenyl ether
-
Methyllithium displaces a phenyl anion from 10-phenyl-10H-phenoxaphosphine to produce a 70:30 mixture of 10-methyl-10H-phenoxaphosphine and starting phosphine. Butyllithium gives 50% conversion to 10-butyl-10H-phenoxaphosphine. These reactions could take place either by a one-step nucleophilic displacement or by ring cleavage followed by recyclization. To show the feasibility of the two-step process, non-heterocyclic lithiated tertiary phosphines were generated and shown to cyclize to phenoxaphosphines. For example, reaction of 2-phenoxyphenyldiphenylphospnine with phenyllithium produced 10-phenyl-10H-phenoxaphosphine (by lithiation ortho to oxygen followed by cyclization) along with triphenylphosphine (by direct displacement of 2-lithiodiphenyl ether). Other compounds prepared in this work: 2,2′-bis(diphenylphosphino)-diphenyl ether, bis(2-phenoxyphenyl)phenylphospnine, tris(2-phenoxyphenyl)phosphine, 4-carboxy-10-phenyl-10H-phenoxaphosphine, and the oxides and sulfides of the phosphines.
- Levy, Jack B.,Walton, Richard C.,Olsen, Ron E.,Symmes Jr., Courtland
-
p. 545 - 548
(2007/10/03)
-
