DFT calculations of pentalenoquinones: towards the interception of 2-bromopentalene-1,5-dione

Download

index.pdf

Date

2008-01-01

Author

Atalar, Taner
Algi, Fatih
Balcı, Metin

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

286
views

62
downloads

To reveal the stability and the aromatic character of pentalenoquinones (PQs) 1-4 and the corresponding bromo derivatives (Br-PQs) 6-9, DFT calculations (B3LYP/6-311+G(d,p)) concerning the geometry optimization, total energy and nucleus independent chemical shift (NICS) values were performed. It was found that all of the compounds have planar geometry. As the energy difference between HOMO-LUMO energy levels (Delta epsilon=epsilon(LUMO) - epsilon(HOMO)) and total energies were considered for the pentalene family, the stability order was found to be 1 > 2 > 3 > 4 for PQs, and 6 > 7 > 8 > 9 for Br-PQs. Furthermore 2-bromopentalene-1,5-dione (6) in solution was investigated and noted that it was too reactive to be isolated or even trapped.

Subject Keywords

Organic Chemistry

URI

https://hdl.handle.net/11511/57100

Journal

ARKIVOC

DOI

https://doi.org/10.3998/ark.5550190.0009.e28

Collections

Graduate School of Natural and Applied Sciences, Article

Suggestions

OpenMETU
Core

Asymmetric synthesis of N-aryl substituted chiral 1,4-aminoalcohol derivatives and applications in various asymmetric transformation reactions Odabaş, Serhat; Tanyeli, Cihangir; Department of Chemistry (2007) The asymmetric synthesis of N-aryl substituted chiral 1,4-aminoalcohols and their applications in asymmetric borane reduction and enantioselective diethylzinc addition to benzaldehyde reactions were performed starting from meso-anhydride 51 that is the cycloadduct of cyclopentadiene and maleic anhydride. The desymmetrization of meso-anhydride 51 was achieved by using quinine or quinidine with very high enantiomeric excess value (up to 98% ee) and with high chemical yield. The quinine-mediated desymmetrizati...
Fam-zinc catalyzed asymmetric 1,3-dipolar cycloaddition reactions of azomethine ylides and Koyuncu, Hasan; Doğan, Özdemir; Department of Chemistry (2007) In the first part of this study, four new chiral ligands (FAM) were synthesized and used in catalytic amounts in asymmetric 1,3-dipolar cycloaddition reactions of azomethine ylides. This method leads to the synthesis of chiral pyrrolidines, which are found in the structure of many biologically active natural compounds and drugs. It was found that using 10 mol% of one of these chiral ligands with different dipolarophiles (dimethyl maleate, dimethyl fumarate, methyl acrylate, tert-butyl acrylate, and Nmethylm...
Asymmetric synthesis of norbornene based 1,4-Aminoalcohol derivatives and applications in asymmetric diethylzinc reactions Erdem, Mine; Tanyeli, Cihangir; Department of Chemistry (2007) The asymmetric synthesis of chiral norbornene based 1,4-aminoalcohols and their applications in asymmetric diethylzinc addition reactions was perfomed starting from meso-anhydride 50. The desymmetrization of this meso-anhydride 50 was done by the usage of quinine or quinidine cinchona alkaloids with very high enantiomeric excess values (up to 98% ee) and chemical yields. The Quinidine-mediated desymmetrization of meso-anhydride 50 with methanol gave (2R,3S)-(+)-cis-monoester 51. The amination of this result...
Transition structures, energetics, and nucleus-independent chemical shifts for divinylcyclobutene-to-cyclooctatriene rearrangement: A DFT study Zora, Metin (American Chemical Society (ACS), 2004-02-06) The minimum energy reaction paths and nucleus-independent chemical shifts (NICS) for the Cope rearrangement of cis-3,4-divinylcyclobutene, obtained by (U)B3LYP/6-31G* calculations, are reported. Three transition structures (endo-boatlike, chairlike, and exo-boatlike) have been located, giving rise to formation of cis,cis,cis-, cis,cis,trans-, and trans,cis, trans- 1, 3,5-cyclooctatrienes, respectively. The minimum energy path proceeds through an endo-boatlike, aromatic transition structure. The reaction pat...
Naphthazarin-Polycyclic Conjugated Hydrocarbons and Iptycenes Dengiz, Çağatay; GUTIERREZ, Gregory D.; SWAGER, Timothy M. (American Chemical Society (ACS), 2017-07-21) The synthesis of a set of naphthazarin-containing polycyclic conjugated hydrocarbons is described herein. Sequential Diels-Alder reactions on a tautomerized naphthazarin core were employed to access the final conjugated systems. Complete conjugation across the backbone can be achieved through complexation with BF2, as observed by (HNMR)-H-1 analysis and UV/vis spectroscopy. Precise synthetic control over the degree of oxidation of naphthazarin quinone Diels-Alder adduct 10 is additionally demonstrated and e...

Citation Formats

T. Atalar, F. Algi, and M. Balcı, “DFT calculations of pentalenoquinones: towards the interception of 2-bromopentalene-1,5-dione,” ARKIVOC, pp. 303–335, 2008, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/57100.