Search citation statements

Order By: Relevance

Paper Sections

Select...
2
2
1

Citation Types

3
25
0

Year Published

2002
2002
2021
2021

Publication Types

Select...
5

Relationship

1
4

Authors

Journals

citations
Cited by 13 publications
(28 citation statements)
references
References 7 publications
3
25
0
Order By: Relevance
“…The simulations have been performed at the same level of theory employed to investigate the formyl cation in SbF 5 /HF. The HCTH exchange and correlation along with a PW basis set gives for the models considered by Esteves et al [112,113], structures and activation energies for the H/H exchange reactions very similar to those obtained by these authors. For instance, for SbF À 6 : H the activation energy computed at 298.15 K is DE ≥ 78.1 kJmol À1 at HCTH/PW and DE ≥ 70.3 kJmol À1 at B3LYP/6-31 G** level, respectively.…”
Section: Formyl Cation Reaction Channelssupporting
confidence: 75%
See 1 more Smart Citation
“…The simulations have been performed at the same level of theory employed to investigate the formyl cation in SbF 5 /HF. The HCTH exchange and correlation along with a PW basis set gives for the models considered by Esteves et al [112,113], structures and activation energies for the H/H exchange reactions very similar to those obtained by these authors. For instance, for SbF À 6 : H the activation energy computed at 298.15 K is DE ≥ 78.1 kJmol À1 at HCTH/PW and DE ≥ 70.3 kJmol À1 at B3LYP/6-31 G** level, respectively.…”
Section: Formyl Cation Reaction Channelssupporting
confidence: 75%
“…There have been relatively few theoretical studies of alkene protonation using realistic models of liquid superacid media [112 ± 115]. Recently, Esteves et al [112,113] studied the protonation of C-H and C-C bonds of methane, ethane, propane, and isobutane in SbF 5 /HF clusters at B3LYP/6-31 G** level with a relativistic core potential for Sb. The superacid moiety was modeled as SbF 5 :HFand Sb 2 F À 11 : H 2 F complexes.…”
Section: Formyl Cation Reaction Channelsmentioning
confidence: 99%
“…On the basis of the different hydrogen–deuterium reactivity found experimentally between conditions with Sb V , oleum, and 98% sulfuric acid, we examined the relative barriers for concerted hydrogen–deuterium exchange that could proceed without formation of discrete [Sb V (HSO 4 ) 6 ] − [CH 5 ] + . Consistent with hydrogen–deuterium exchange experiments, the calculated Gibbs barrier for proton exchange between H 2 SO 4 (98% H 2 SO 4 ) and methane without free SO 3 is 40.8 kcal/mol (see SI for transition-state structure). Consistent with the faster exchange when SO 3 is added, introduction of a single SO 3 Lewis acid coordinated to the S=O group in H 2 SO 4 in this proton exchange transition state lowers the Gibbs activation energy to 34.0 kcal/mol. We also located a transition state for proton exchange by (H 2 SO 4 )­Sb V (HSO 4 ) 5 , which has a Gibbs energy barrier of only 28.4 kcal/mol.…”
Section: Results and Discussionmentioning
confidence: 57%
“…Perhaps the most important comparative pathway is the possibility of superacid protonolysis reactivity to generate [CH 5 ] + (Pathway B in Scheme a) since H 2 SO 4 containing SO 3 is a superacid and the presence of Sb V , a strong Lewis acid, can further increase the acidity of the solvent. It is generally assumed that if [CH 5 ] + is formed through CH 4 protonolysis, then any [CH 3 ] + that is generated would lead to carbo-oligomerization. However, there is also the possibility that if [CH 3 ] + is generated it is rapidly captured by sulfuric acid or bisulfate to irreversibly generate methyl bisulfate. Therefore, it was critical to determine if [CH 3 ] + could be feasibly generated by protonolysis by (H 2 SO 4 )­Sb V (HSO 4 ) 5 1 in H 2 SO 4 /SO 3 .…”
Section: Results and Discussionmentioning
confidence: 99%
“…Due to its extreme acidity, it is not hard to understand the complexity and difficulty in the corresponding experimental measurement of superacid arising from the high requirement for both the equipment and operation. Therefore, theoretical calculations have become more and more important in the study on superacid systems. , Reliable prediction on superacid, obtained from theoretical calculations, could provide an effective guide for the subsequent experiments and thus could increase the efficiency of the research. In fact, theoretical calculation has already played an important role in the field of superacids in recent years. , …”
Section: Introductionmentioning
confidence: 99%