scholarly journals Diels-Alder cycloadditions of 1,3-cyclohexadien-4,5-diones (obenzoquinones) with norbornadiene. Part II. A high level computational study of their stereospecificities

2000 ◽  
Author(s):  
Davor Margetic ◽  
Martin Johnston ◽  
Melissa Latter ◽  
Ronald Warrener
Keyword(s):  
Computational Study ◽  
Diels Alder ◽  
High Level

scholarly journals A computational study for the reaction mechanism of metal-free cyanomethylation of aryl alkynoates with acetonitrile

RSC Advances ◽  
2021 ◽  
Vol 11 (30) ◽  
pp. 18246-18251
Author(s):  
Selçuk Eşsiz
Keyword(s):  
Density Functional Theory ◽  
Reaction Mechanism ◽  
Density Functional ◽  
Computational Study ◽  
Coupled Cluster ◽  
Functional Theory ◽  
Metal Free ◽  
Coupled Cluster Methods ◽  
High Level ◽  
Cluster Methods

A computational study of metal-free cyanomethylation and cyclization of aryl alkynoates with acetonitrile is carried out employing density functional theory and high-level coupled-cluster methods, such as [CCSD(T)].

scholarly journals Density Functional Theory and Complete Basis Set Ab Initio Computational Study of Five-, Six-, Seven- and Eight-hydrogen Coordinated Carbon Cations

1999 ◽  
Vol 23 (8) ◽  
pp. 502-503
Author(s):  
Branko S. Jursic
Keyword(s):  
Density Functional Theory ◽  
Ab Initio ◽  
Density Functional ◽  
Computational Study ◽  
Basis Set ◽  
Functional Theory ◽  
Complete Basis ◽  
Complete Basis Set ◽  
High Level

High level ab initio and density functional theory studies are performed on highly protonated methane species.

On the Mechanism of Au‐catalyzed Enynamide‐Yne Dehydro‐Diels‐Alder Reactions: An Experimental and Computational Study

2021 ◽  
Author(s):  
David Fabian León Rayo ◽  
Young J. Hong ◽  
Dominic Campeau ◽  
Dean J. Tantillo ◽  
Fabien Gagosz
Keyword(s):  
Computational Study ◽  
Diels Alder

A computational study towards the reactivity of 2-(2-ethynylphenyl-X-)pyrimidines in intramolecular Diels-Alder reactions.

Tetrahedron ◽  
1991 ◽  
Vol 47 (9) ◽  
pp. 1753-1764 ◽  
Author(s):  
W.A.W. Stolle ◽  
A.T.M. Marcelis ◽  
H.C. van der Plas
Keyword(s):  
Computational Study ◽  
Diels Alder

Intramolecular Diels-Alder reactions of pyrimidines and a computational study toward their structure and reactivity

1992 ◽  
Vol 57 (11) ◽  
pp. 3000-3007 ◽  
Author(s):  
Werner A. W. Stolle ◽  
August E. Frissen ◽  
Antonius T. M. Marcelis ◽  
Henk C. Van der Plas
Keyword(s):  
Computational Study ◽  
Diels Alder

Computational Study for Inventory Estimation of Se-79, Tc-99, Sn-126, and Cs-135 in High-Level Radioactive Wastes From Spent Nuclear Fuels of Light Water Reactors

2011 ◽  
Author(s):  
Keisuke Okumura ◽  
Shiho Asai ◽  
Yukiko Hanzawa ◽  
Tsutomu Okamoto ◽  
Hideya Suzuki ◽  
...  
Keyword(s):  
Parametric Study ◽  
Computational Study ◽  
Estimation Method ◽  
Fission Products ◽  
Radioactive Wastes ◽  
Light Water Reactors ◽  
Nuclear Fuels ◽  
Light Water ◽  
Water Reactors ◽  
High Level

Inventory estimation of long-lived fission products (LLFPs) in high-level radioactive wastes (HLW) from spent nuclear fuels of light water reactors is important for a safety assessment of their disposal. In order to develop an inventory estimation method of difficult-to-measure LLFPs (Se-79, Tc-99, Sn-126, and Cs-135), a parametric study was carried out by using a sophisticated burnup calculation code and data. In the parametric study, fuel specifications and irradiation conditions are changed in the conceivable range. The considered parameters are fuel assembly types (PWR / BWR), U-235 enrichment, moderator temperature, void fraction, power density, and so on. From the calculated results, we clarify the burnup characteristics of the target LLFPs and their possible ranges of generations. Finally, candidates of the key nuclide are proposed for the scaling factor method of HLW.

On the possibility of conversion of strained bridgehead alkenes into carbenes via 1,2 hydrogen and 1,2 carbon migrations. A theoretical study of the rearrangements in the adamantene and protoadamantene systems

1998 ◽  
Vol 76 (6) ◽  
pp. 851-861 ◽  
Author(s):  
Gennady V Shustov ◽  
Michael TH Liu
Keyword(s):  
Experimental Data ◽  
Ab Initio ◽  
Theoretical Study ◽  
Activation Barrier ◽  
Main Channel ◽  
Diels Alder ◽  
Activation Barriers ◽  
Ab Initio Computation ◽  
Carbon Migration ◽  
High Level

Rearrangements of 2-adamantene 3, adamantylidene 4, and 4-protoadamantylidene 5 have been studied theoretically using high level ab initio computations. Adamantene 3 and adamantylidene 4 have singlet ground states. The conversion of 3 into 4 via 1,2 hydrogen migration ( Δ Gdouble dagger = 69.1 kcal mol-1) cannot compete with 1,2 carbon migration of 3 to 5 (30.3 kcal mol-1). The singlet carbene 5 rearranges to 2,4-dehydroadamantane 6 and 4,5-protoadamantene 9 via 1,3H and 1,2H shifts, respectively, with identical activation barriers of 8.8 kcal mol-1. The 1,2 migration of the bridge hydrogen in 5 leading to 3,4 protoadamantene 8 has a higher activation barrier (37.2 kcal mol-1). A retro Diels-Alder cycloaddition of 3 to 5-allyl-3-methylenecyclohex-1-ene 7 is the main channel of the unimolecular conversion of 3 ( Δ Gdouble dagger = 20.5 kcal mol-1). A predicted ratio of 7 > > 6 approx 9 of the products of thermolysis of 3 is in agreement with experimental data. The rearrangement of 4 into 6 via the 1,3H shift ( Δ Gdouble dagger = 11.8 kcal mol-1) dominates over the 1,2C shift of 4 to 8 (13.5 kcal mol-1), also in accord with experiment.Key words: adamantene, protoadamantenes, carbenes, rearrangements, ab initio, computation.

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