scholarly journals New Rigid Polycyclic Bis(phosphane) for Asymmetric Catalysis

Molecules ◽  
2019 ◽  
Vol 24 (3) ◽  
pp. 571 ◽  
Author(s):  
K. Pietrusiewicz ◽  
Katarzyna Szwaczko ◽  
Barbara Mirosław ◽  
Izabela Dybała ◽  
Radomir Jasiński ◽  
...  
Keyword(s):  
Asymmetric Catalysis ◽  
Palladium Catalysts ◽  
Density Functional ◽  
Bond Activation ◽  
Palladium Complexes ◽  
Efficient Synthesis ◽  
Phosphorus Ligands ◽  
Functional Theory ◽  
Asymmetric Transformations ◽  
Structural Database

A simple, highly efficient synthesis of a series of novel chiral non-racemic rigid tetracyclic phosphorus ligands, applicable in important chemical asymmetric transformations, was performed. In a tandem cross-coupling/C-H bond activation reaction, a well-recognised and readily available ligand (R,R)-NORPHOS was used as the starting material. The palladium complexes of new ligands were obtained and characterised on the example of a crystalline dichloropalladium complex of [(1R,2R,9S,10S,11R,12R)-4-phenyltetracyclo[8.2.1.02,9.03,8]trideca-3,5,7-triene-11,12-diyl]bis(diphenylphosphane). A notably high activity and stereoselectivity of the palladium catalysts based on the new ligands were confirmed in a model asymmetric allylic substitution reaction. Herein, we discuss the geometry of the palladium complexes formed and its impact on the efficiency of the catalysts. A comparison of their geometric features with other bis(phosphane) ligand complexes found in the Cambridge Structural Database and built density functional theory (DFT) commutated models is also presented and rationalised.

Mechanistic insights into α-branched amines formation with pivalic acid assisted C−H bond activation catalysed by Cp*Rh complexes

2021 ◽  
Author(s):  
Rongrong Li ◽  
Xinzheng Yang
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Bond Activation ◽  
Pivalic Acid ◽  
Activation Mechanism ◽  
Functional Theory ◽  
Density Functional Theory Computations ◽  
Reaction Energies

Density functional theory computations revealed a pivalic acid assisted C−H bond activation mechanism for rhodium catalyzed formation of α-branched amines with C−C and C−N bond couplings. The reaction energies of...

Adsorption mechanism of CO molecule on Al(111) surface: periodic DFT investigation

2018 ◽  
Vol 96 (12) ◽  
pp. 993-999 ◽  
Author(s):  
Chenhong Xu ◽  
Suqin Zhou ◽  
Jing Chen ◽  
Yuxiang Wang ◽  
Lei He
Keyword(s):  
Charge Transfer ◽  
Density Functional ◽  
Adsorption Mechanism ◽  
Bond Activation ◽  
Aluminum Surface ◽  
Hollow Site ◽  
Functional Theory ◽  
Wide Range ◽  
Adsorption Of Co ◽  
Adsorption Energies

The adsorption mechanism of the CO molecule on Al(111) surface has been investigated systematically at the atom-molecule level by the method of periodic density functional theory. The adsorption energies, adsorption structures, charge transfer, and density of states have been calculated in a wide range of coverage. It is found that the hcp-hollow site is the energetically favorable site. A significant positive correlation has been found between the adsorption energy (Eads) and coverage. The adsorbed CO molecules are almost perpendicular on the surface with the C atom facing the surface. There is an obvious charge transfer from Al atoms to the C atom; the Al atoms that have interaction with the C atom offer the most charge. The 4σ, 1π, and 5σ molecular orbitals of CO are found to contribute to bonding with the Al. The charges filling in the 2π molecular orbital contribute to C–O bond activation. In conclusion, the passivation of aluminum surface and the activation of CO molecule occur simultaneously in the adsorption of CO on Al surface.

On the role of the surface oxygen species during A–H (A = C, N, O) bond activation: a density functional theory study

2015 ◽  
Vol 51 (13) ◽  
pp. 2621-2624 ◽  
Author(s):  
Jong Suk Yoo ◽  
Tuhin S. Khan ◽  
Frank Abild-Pedersen ◽  
Jens K. Nørskov ◽  
Felix Studt
Keyword(s):  
Density Functional ◽  
Bond Activation ◽  
Bond Cleavage ◽  
Oxygen Species ◽  
Final States ◽  
Surface Oxygen ◽  
Density Functional Theory Study ◽  
Reaction Energy ◽  
Functional Theory

During A–H (A = C, N, O) bond cleavage on O* or OH* pre-covered (111) surfaces, the oxygen species play the role of modifying the reaction energy by changing the species involved in the initial and final states of the reaction.

Does a multiply bonded oxo ligand directly participate in B–H bond activation by a high-valent di-oxo-molybdenum(vi) complex? A density functional theory study

2015 ◽  
Vol 5 (6) ◽  
pp. 3259-3269 ◽  
Author(s):  
Liangfang Huang ◽  
Jiandi Wang ◽  
Xiaoqin Wei ◽  
Haiyan Wei
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Bond Activation ◽  
Organic Substrates ◽  
Density Functional Theory Study ◽  
Molybdenum Complex ◽  
Functional Theory ◽  
Multiply Bonded ◽  
High Valent ◽  
Oxo Ligand

The multiply bonded oxo ligand does not participate in the activation of the B–H bond with organic substrates of amides, amines, and nitriles by the high-valent oxo-molybdenum complex MoO2Cl2.

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