On the planarity of styrene and its derivatives: the molecular structures of styrene and (Z)-β-bromostyrene as determined by ab initio calculations and gas-phase electron diffraction

Cochran, John C.; Hagen, Kolbjørn; Paulen, G.; Shen, Quang; Tom, Samson; Trætteberg, M.; Wells, Christopher

doi:10.1016/s0022-2860(97)00071-9

Cited by 36 publications

(32 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The near-planar geometry around these bonds corresponds to the situation in styrene, for which torsion angles of the same order of magnitude have been reported. [18,20] Both the butadiene and the styrene substructures suggest that 1 should be regarded as being composed of two α,α-linked styrene units, rather than as a disubstituted butadiene. This is supported by the C12-C22 bond length of 1.492(2) Å.…”

Section: Resultsmentioning

confidence: 99%

On the Structure of Cross‐Conjugated 2,3‐Diphenylbutadiene

Walree¹,

Wiel²,

Jenneskens³

et al. 2007

Eur J Org Chem

View full text Add to dashboard Cite

The structure of the cross-conjugated compound 2,3-diphenylbutadiene was investigated by single-crystal X-ray diffraction and computational methods. In the crystal structure the central butadiene fragment adopts an s-gauche geometry [-55.6(2)°torsion angle φ around the essential single bond], whereas the styrene moieties are close to planarity. MP2/6-311G* calculations show that the s-gauche conformation represents the global minimum along the φ coordinate, but also revealed the existence of an s-trans local minimum.

show abstract

Section: Resultsmentioning

confidence: 99%

On the Structure of Cross‐Conjugated 2,3‐Diphenylbutadiene

Walree¹,

Wiel²,

Jenneskens³

et al. 2007

Eur J Org Chem

View full text Add to dashboard Cite

show abstract

“…This structure may be modified in the adsorbed state. The lowest energy structure of St in the gas phase is flat with the π-orbitals both of the phenyl-and the vinyl-group forming a common conjugated system, but bending of the vinyl-group does not cost much energy [360]. That St is chemisorbed more strongly than EB on Fe 3 O 4 (111) and Fe 2 O 3 (0001), suggests a more extended π-system in St with the phenyl-and the vinyl-group in one plane …”

Section: 29) (B) E Des Vs D O-mentioning

confidence: 96%

Surface chemistry and catalysis on well-defined epitaxial iron-oxide layers

Weiß

Ranke

2002

Progress in Surface Science

584

610

View full text Add to dashboard Cite

Metal-oxide based catalysts are used for many important synthesis reactions in the chemical industry. A better understanding of the catalyst operation can be achieved by studying elemantary reaction steps on well-defined model catalyst systems. For the dehydrogenation of ethylbenzene to styrene in the presence of steam both unpromoted and potassium promoted iron-oxide catalysts are active. Here we review the work done over unpromoted single-crystalline FeO(111), Fe 3 O 4 (111) and α-Fe 2 O 3 (0001) films grown epitaxially on Pt(111) substrates. Their geometric and electronic surface structures were characterized by STM, LEED, electron microscopy and electron spectroscopic techniques. In an integrative approach, the interaction of water, ethylbenzene and styrene with these films was investigated mainly by thermal desorption and photoelectron emission spectroscopy. The adsorptiondesorption energetics and kinetics depend on the oxide surface terminations and are correlated to the electronic structures and acid-base properties of the corresponding oxide phases, which reveal insight into the nature of the active sites and into the catalytic function of semiconducting oxides in general. Catalytic studies, using a batch reactor arrangement at high gas pressures and post reaction surface analysis, showed that only α-Fe 2 O 3 (0001) containing surface defects is catalytically active, whereas Fe 3 O 4 (111) is always inactive. This can be related to the elementary adsorption and desorption properties observed in ultrahigh vacuum, which indicates that the surface chemical properties of the iron-oxide films do not change significantly across the "pressure-gap". A model is proposed according to which the active site involves a regular acidic surface sites and a defect site next to it. The results on metal-oxide surface chemistry also have implications for other fields, such as environmental science, biophysics and chemical sensors.-2 -"2kyEi9FYSQjBVrZxIPQ.FHIAC_WRa02_review.doc", Datum: 19.02.03

show abstract

“…9,25 Note that it has been assumed that the fragment structures do not change as they rotate about the ring-ene bond. The calculations by Cochrane et al 3 find that there are small changes as the angle changes, but these are confined to the region near ϭ0°, and the same calculations find that the molecule spends most time with ϭ27°. Consequently, it is reasonable to neglect such geometrical distortions in the con- …”

Section: Structure Of the Ene Fragmentmentioning

confidence: 97%

Is styrene planar in liquid phases?

Celebre

Longeri

et al. 2004

The Journal of Chemical Physics

View full text Add to dashboard Cite

The proton NMR spectra of two 13 C-labeled isotopomers of styrene dissolved in two liquid crystalline solvents have been obtained and analyzed to yield four sets each of 24 dipolar couplings. These couplings were then used to investigate the structure of the ring and the ene fragments of the molecule, and the position of the maximum, 0 , in the ring-ene bond rotational probability distribution. To do this, the effect on the dipolar couplings of small-amplitude vibrational motion was taken into account using vibrational wave functions calculated by molecular orbital and density functional methods. It is concluded that the NMR data are consistent with the ring fragment, averaged over the ring-ene rotation, planar, while the ene fragment is not. The value of 0 is found to be 18.0°Ϯ0.2°for the two solutions, compared with a value of 27°calculated by the molecular method MP2/6-31G*.

show abstract

On the planarity of styrene and its derivatives: the molecular structures of styrene and (Z)-β-bromostyrene as determined by ab initio calculations and gas-phase electron diffraction

Cited by 36 publications

References 42 publications

On the Structure of Cross‐Conjugated 2,3‐Diphenylbutadiene

On the Structure of Cross‐Conjugated 2,3‐Diphenylbutadiene

Surface chemistry and catalysis on well-defined epitaxial iron-oxide layers

Is styrene planar in liquid phases?

Contact Info

Product

Resources

About