&lt;i&gt;Ab initio&lt;/i&gt; and DFT Study of Prototropic and Metallotropic 1,5-Shifts of Isolobal Cyclopentadienyl Derivatives

Javanshir, Zahra; Jameh‐Bozorghi, Saeed; Namdari, Ali-Reza

doi:10.18520/cs/v112/i04/743-749

Cited by 2 publications

(1 citation statement)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The only difference is that on one of the reagents, both new bonds are being made to the same atom [3]. To study the molecular mechanisms of a wide range of organic reactions been investigated, such as Cope rearrangements, Diels-Alder, 1,3-dipolar and other cycloadditions, the Friedel-Crafts reaction, the Staudinger reaction [4][5][6][7][8][9][10][11][12][13][14][15][16].…”

Section: Introductionmentioning

confidence: 99%

DFT calculations of the neighboring groups effects on cheletropic reaction of 2,5-Dihydrothiophene sulfone

2018

View full text Add to dashboard Cite

In this research DFT calculations were used to investigate the neighboring effects on cheletropic reaction of 2,5-Dihydrothiophene sulfone (1). Structural properties and stereoelectronic behavior in the activation energy and enthalpy of cheletropic reaction were performed for 2,5-Dihydrothiophene sulfone where substitutions of CF3; CCl3 and CBr3 that were placed on Sulfolen were investigated using DFT-B3LYP/6-311+G** level of theory. The Results of calculations using B3LYP, HF and MP2 [basic 6-311+G**] showed that the trend of electronic effects on the cis and trans state is different. Reaction rate and activation energy in cis compounds showed that increasing electronegativity and decreasing the band length reduced the reaction speed. Trend of reaction rate and activation energy in trans compounds showed that in cheletropic reaction rate and activation energy not only electronic effects but also the Steric effects play a main role. DFT/B3LYP/6-311+G** calculation results also confirm these results. In cis compounds, 2,5-three Floro metyl Sulfolen (2) has the highest activation energy about (12.25 kcal/mol) and the lowest rate of reaction. In trans compounds, Trans-2,5-three chloro metyl Sulfolen (7) has the highest activation energy about (12.99 kcal/mol) and the lowest rate of reaction.

show abstract

Section: Introductionmentioning

confidence: 99%

DFT calculations of the neighboring groups effects on cheletropic reaction of 2,5-Dihydrothiophene sulfone

2018

View full text Add to dashboard Cite

show abstract

Probing Reaction Mechanism of [1,5]‐Migration in Pyrrolium and Pyrrole Derivatives: Activation of a Stronger Bond in Electropositive Groups Becomes Easier

Xie

Zhao

Chen

et al. 2019

Chemistry An Asian Journal

View full text Add to dashboard Cite

The [1,5]-migration reaction has attractedc onsiderable attention from experimentalists andt heoreticians for decades. Although it has been extensively investigated in various systems, studies on pyrrolium derivatives are underdeveloped. Herein, at heoretical study on the reaction mechanism of [1,5]-migrationi nb oth pyrroliuma nd pyrrole derivatives is presented. The results reveal lower activation barriers in [1,5]-migration of electropositive groups (AuPMe 3 and SnH 3 )i np yrrolium derivatives, although the bond dissociation energies of the AuÀNb ond (98.8 kcal mol À1 )a nd SnÀN bond (81.7 kcal mol À1 )a re larger than that of the NÀFb ond (57.6 kcal mol À1 ). The unexpectedly lower activation barriers (4.5 and 4.9 kcal mol À1 for AuPMe 3 and SnH 3 ,r espectively) for [1,5]-migration of electropositive groups,i nc omparison with the [1,5]-fluorine shift, can be attributed to aromaticity stabilizing the transition states, as revealed by significantly negative nucleus-independent chemical shift (NICS) values. Further studies indicate that charge distribution and frontier molecular orbitals also plays ome roles in [1,5]-migration of pyrrolium derivatives.[a] Q.

show abstract

<i>Ab initio</i> and DFT Study of Prototropic and Metallotropic 1,5-Shifts of Isolobal Cyclopentadienyl Derivatives

Abstract: The structures, energies and sigmatropic behaviour of  1 -cyclopenta-2,4-dienylborane (1) and  1 -cyclopentadiene-three carbonyl cobalt (I) (2) were examined using DFT-B3LYP/6-311+G** level of theory. Both

Cited by 2 publications

References 16 publications

DFT calculations of the neighboring groups effects on cheletropic reaction of 2,5-Dihydrothiophene sulfone

DFT calculations of the neighboring groups effects on cheletropic reaction of 2,5-Dihydrothiophene sulfone

Probing Reaction Mechanism of [1,5]‐Migration in Pyrrolium and Pyrrole Derivatives: Activation of a Stronger Bond in Electropositive Groups Becomes Easier

Contact Info

Product

Resources

About