scholarly journals A density functional theory study on the mechanism of the allylpalladium-catalyzed dehydrogenation of aldehydes and cyclic ketones

2021 ◽  
Vol 46 ◽  
pp. 146867832110206
Author(s):  
Anan Haj Ichia Arisha
Keyword(s):  
Density Functional Theory ◽  
Gas Phase ◽  
Density Functional ◽  
Transition States ◽  
Density Functional Theory Calculations ◽  
Carbonyl Complex ◽  
Cyclic Ketones ◽  
Complex Catalyst ◽  
Functional Theory ◽  
Hydride Elimination

The results of density functional theory calculations at the APFD/SDD level are detailed herein in order to study the main steps in the α,β-dehydrogenation of aldehydes and cyclic ketones in the presence of an allylpalladium complex catalyst. The mechanism is believed to proceed via an allylpalladium enolate complex (A) in equilibrium with the carbon-bonded complex (B), followed by β-hydride elimination to yield the allylpalladium hydride coordinated to the α,β-unsaturated carbonyl (complex C). The optimized structures and detailed energy profiles of these intermediates and their corresponding transition states are presented herein. The results indicate that the intermediates and their transition states are more stable in THF solution than in the gas phase. In detail, the energy barriers for the two steps are found to be 25.22 and 11.13 kcal/mol, respectively, in THF, and 29.93 and 9.77 kcal/mol, respectively, in the gas phase.

scholarly journals Formation and reactions of the 1, 8-naphthyridine (napy) ligated geminally dimetallated phenyl complexes [(napy)Cu2(Ph)]+, [(napy)Ag2(Ph)]+ and [(napy)CuAg(Ph)]+

2019 ◽  
Vol 25 (1) ◽  
pp. 30-43 ◽  
Author(s):  
Qiuyan Jin ◽  
Jiaye Li ◽  
Alireza Ariafard ◽  
Allan J Canty ◽  
Richard AJ O’Hair
Keyword(s):  
Density Functional Theory ◽  
Gas Phase ◽  
Density Functional ◽  
Ion Trap ◽  
Density Functional Theory Calculations ◽  
Collision Induced Dissociation ◽  
Ion Trap Mass Spectrometry ◽  
Functional Theory ◽  
Organometallic Cations ◽  
Gas Phase Ion

Gas-phase ion trap mass spectrometry experiments and density functional theory calculations have been used to examine the routes to the formation of the 1,8-naphthyridine (napy) ligated geminally dimetallated phenyl complexes [(napy)Cu2(Ph)]+, [(napy)Ag2(Ph)]+ and [(napy)CuAg(Ph)]+ via extrusion of CO2 or SO2 under collision-induced dissociation conditions from their corresponding precursor complexes [(napy)Cu2(O2CPh)]+, [(napy)Ag2(O2CPh)]+, [(napy)CuAg(O2CPh)]+ and [(napy)Cu2(O2SPh)]+, [(napy)Ag2(O2SPh)]+, [(napy)CuAg(O2SPh)]+. Desulfination was found to be more facile than decarboxylation. Density functional theory calculations reveal that extrusion proceeds via two transition states: TS1 enables isomerization of the O, O-bridged benzoate to its O-bound form; TS2 involves extrusion of CO2 or SO2 with the concomitant formation of the organometallic cation and has the highest barrier. Of all the organometallic cations, only [(napy)Cu2(Ph)]+ reacts with water via hydrolysis to give [(napy)Cu2(OH)]+, consistent with density functional theory calculations which show that hydrolysis proceeds via the initial formation of the adduct [(napy)Cu2(Ph)(H2O)]+ which then proceeds via TS3 in which the coordinated H2O is deprotonated by the coordinated phenyl anion to give the product complex [(napy)Cu2(OH)(C6H6)]+, which then loses benzene.

Nb2BN2− cluster anions reduce four carbon dioxide molecules: reactivity enhancement by ligands

2020 ◽  
Vol 49 (40) ◽  
pp. 14081-14087 ◽  
Author(s):  
Hai-Yan Zhou ◽  
Ming Wang ◽  
Yong-Qi Ding ◽  
Jia-Bi Ma
Keyword(s):  
Mass Spectrometry ◽  
Carbon Dioxide ◽  
Density Functional Theory ◽  
Gas Phase ◽  
Density Functional ◽  
Density Functional Theory Calculations ◽  
Cluster Anions ◽  
Gas Phase Reactions ◽  
Functional Theory ◽  
Flight Mass Spectrometry

The thermal gas-phase reactions of Nb2BN2− cluster anions with carbon dioxide have been explored by using the art of time-of-flight mass spectrometry and density functional theory calculations.

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