Gas phase and solid state X-ray photoelectron spectra of the substituted acetylenes (SF5)n C2 (CF3)2−n (n = 0, 1, 2): A comparison of the pentafluorosulfur and trifluoromethyl groups

The preparation of the N-(2-hydroxypropyl)-N-alkylhydroxylamines, 6a (R = CH3) and 6b (R = CH2Ph), and their reactions with phenylboronic acid are described. Regardless of the molar ratios of reactants employed, the reaction with 6b leads to the 1:2 condensate 1-benzyl-7-methyl-3,5-diphenyl-2,4,6-trioxa-1-azonia-3-bora-5-boratabicyclo[3.3.0]octane, 7, while that with 6a gives rise to the 1:1 condensate 1,4,6,9-tetramethyl-2,7-diphenyl-3,8,11,12-tetraoxa-1,6-diazonia-2,7-diboratatricyclo[5.3.1. 12,6]dodecane, 11 (the cyclic BONBON dimer of 4,6-dimethyl-2-phenyl-1,3-dioxa-4-aza-2-boracyclohexane, 9). Compounds 7 and 11 both crystallize in the triclinic space group [Formula: see text]: for 7; a = 13.126(1), b = 15.337(1), c = 10.9469(5) Å, α = 91.727(5), β = 104.647(5), γ = 72.922(7)°, Z = 4; and for 11; a = 9.0807(4), b = 9.1653(3), c = 6.4876(2) Å, α = 97.708(3), β = 108.830(3), γ = 89.188(4)°, Z = 1. The structures were solved by direct methods and were refined by full-matrix least-squares procedures to R = 0.038 and 0.032 for 5879 and 1827 reflections with I ≥ 3σ(F2), respectively. Compound 7 has the expected bicyclic pyroboronate structure, but represents the first reported N-substituted example of this type of compound. Bond lengths involving boron in 7 are (C) O—B(sp3) = 1.428(2) and 1.420(2), (B)O—B(sp3) = 1.472(2) and 1.468(2), N—B(sp3) = 1.737(2) and 1.762(2), C(phenyl)—B(sp3) = 1.588(2) and 1.584(2), (N)O—B(sp2) = 1.402(2) and 1.404(2), (B)O—B(sp2) = 1.331(2) and 1.329(2), C(phenyl)—B(sp2) = 1.555(3) and 1.553(2) Å. The X-ray analysis establishes a centrosymmetric, twofold N → B coordinated, dimeric structure in the solid state for 11 in which each B—O—N segment of a central six-membered BONBON ring is bridged by an O—C—C moiety. Compound 11 represents the first fully characterized example of a new type of "BONBON" compound. Bond distances involving the boron atom are (N)O—B = 1.465(1), (C)O—B = 1.428(1), N—B = 1.695(2), and C(phenyl)—B = 1.607(2) Å. Spectroscopic evidence indicates that in solution and in the gas phase this material exists predominantly as the monomer 9.

Download Full-text

X-Ray photoelectron spectroscopy of monosubstituted perfluorobenzenes

Canadian Journal of Chemistry ◽

10.1139/v77-177 ◽

1977 ◽

Vol 55 (8) ◽

pp. 1279-1284 ◽

Cited By ~ 6

Author(s):

Barry C. Trudell ◽

S. James W. Price

Keyword(s):

Gas Phase ◽

Photoelectron Spectroscopy ◽

Binding Energies ◽

Photoelectron Spectra ◽

Atomic Charges ◽

X Ray ◽

Sophisticated Analysis ◽

Charge Calculations

The gas phase X-ray photoelectron spectra, XPS, were observed for the series C6F5X (X = F, Cl, I, Br, H). Binding energies were determined from the spectra using the ESCAPLOT Program. Charge calculations were carried out using Equalization of Electronegativity, CNDO/2, and ACHARGE approaches on each molecule. The more sophisticated analysis leads to the following equation correlating the (C 1s) binding energies and the atomic charges qi[Formula: see text]

Download Full-text

Photoelectron spectra and electronic structure of cyanoguanidine in the gas phase and solid state

Journal of the Chemical Society Faraday Transactions 2 Molecular and Chemical Physics ◽

10.1039/f29817700683 ◽

1981 ◽

Vol 77 (4) ◽

pp. 683 ◽

Cited By ~ 4

Author(s):

David Briggs ◽

Martyn F. Guest ◽

Ian H. Hillier ◽

Michael J. Knight ◽

Alastair A. MacDowell

Keyword(s):

Electronic Structure ◽

Solid State ◽

Gas Phase ◽

Photoelectron Spectra

Download Full-text

Configurations and conformations of glycosyl sulfoxides

Canadian Journal of Chemistry ◽

10.1139/v10-091 ◽

2010 ◽

Vol 88 (11) ◽

pp. 1154-1174 ◽

Cited By ~ 6

Author(s):

Hong Liang ◽

Micheline MacKay ◽

T. Bruce Grindley ◽

Katherine N. Robertson ◽

T. Stanley Cameron

Keyword(s):

Solid State ◽

Dft Calculations ◽

Gas Phase ◽

Density Functional ◽

Lone Pair ◽

Azido Group ◽

X Ray Diffraction ◽

X Ray ◽

Comparison Of The Results ◽

P Type

X-ray crystallographic studies of two axial glycosyl sulfoxides having RS configurations (derivatives of phenyl 2-azido-2-deoxy-1-thio-α-d-galactopyranoside S-oxide) show that they adopt anti conformations in the solid state, in contrast to previous observations and assumptions. Density functional theory (DFT) calculations at the B3lYP6–311G+(d,p)/6–31G(d) level confirm that anti conformations of both phenyl and methyl RS glycosyl sulfoxides of 2-azido-2-deoxy-α-d-pyranosides are more stable than exo-anomeric conformations in the gas phase. 1D NOE measurements indicate that the more polar exo-anomeric conformers are only populated to a slight extent in solution. The anti conformations are distorted so that the glycosyl substituents are closer to being eclipsed with H1. This distortion allows S n → σ* overlap if the sulfur lone pair is a p-type lone pair. Evidence for this overlap comes from short C1–S bond distances, as short as the comparable bond distances in the X-ray crystal structure and in the results from DFT calculations for the SS glycoside, which does adopt the expected exo-anomeric conformation, both in the solid state and in solution, and has normal n → σ* overlap. For 2-deoxy derivatives not bearing a 2-azido group, gas-phase DFT calculations at the same level indicate that the anti- and exo-anomeric conformers have comparable stabilities. Comparison of the results of the two series shows that electronegative substituents in equatorial orientations at C2 destabilize conformations with parallel S–O arrangements, the conformation favored by having an endocyclic C–O dipole antiparallel to the S–O dipole, by about 2.5 kcal mol–1 (1 cal = 4.184 J). An equatorial glycosyl sulfoxide, (SS) phenyl 3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-1-thio-β-d-glucopyranoside S-oxide, also adopts an anti conformation in the solid state as shown by X-ray diffraction. It also adopts this conformation in solution, in contrast to studies of other equatorial glycosyl sulfoxides.

Download Full-text

Tris [(trimethylsilyl)oxy] antimony

Zeitschrift für Naturforschung B ◽

10.1515/znb-1994-0701 ◽

1994 ◽

Vol 49 (7) ◽

pp. 855-858 ◽

Cited By ~ 8

Author(s):

Michael Baier ◽

Klaus Angermaier ◽

Hubert Schmidbaur

Keyword(s):

Crystal Structure ◽

Solid State ◽

Gas Phase ◽

Structure Determination ◽

Spectroscopic Data ◽

Mass Spectrometric ◽

Unit Cell ◽

The Other ◽

X Ray ◽

Trigonal Bipyramidal

Abstract Tris[(trimethylsilyl)oxy]antimony (Sb(OSiMe3)3, 1) has been prepared from SbCl3 and 3 equiv. of LiOSiMe3 in diethylether. According to mass spectrometric and NMR spectroscopic data, 1 appears to be a monomer in solution and in the gas phase. Dimerisation occurs, however, in the solid state as verified by an X-ray crystal structure determination. The unit cell contains three crystallographically independent monomers, two of which form one type of dimer, while the other is part of a centrosymmetrical dimer. In both types of dimers two Sb atoms are connected via two OSiMe3 groups to form distorted Sb2O2-squares. Together with the remaining 4 OSiMe3 groups and the two stereochemically active lone pairs, each Sb exhibits a trigonal bipyramidal coordination.

Download Full-text

The application of gas phase and solid state X-ray photoelectron spectroscopy to the investigation of derivatives containing the repeating SN unit

Synthetic Metals ◽

10.1016/0379-6779(80)90007-7 ◽

1980 ◽

Vol 1 (2) ◽

pp. 161-173 ◽

Cited By ~ 4

Author(s):

Patrick Brant ◽

David C. Weber ◽

Curtis T. Ewing ◽

Forrest L. Carter ◽

Joseph A. Hashmall

Keyword(s):

Solid State ◽

Gas Phase ◽

Photoelectron Spectroscopy ◽

X Ray

Download Full-text

Synthesis of Ferromagnetic Germanides in 40Ge/60Mn Films: Magnetic and Structural Properties

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.215.167 ◽

2014 ◽

Vol 215 ◽

pp. 167-172

Author(s):

Victor G. Myagkov ◽

A.A. Matsunin ◽

Y.L. Mikhlin ◽

Victor S. Zhigalov ◽

Liudmila E. Bykova ◽

...

Keyword(s):

Solid State ◽

Curie Temperature ◽

Photoelectron Spectroscopy ◽

Magnetic Measurements ◽

Atomic Ratio ◽

Photoelectron Spectra ◽

Solid State Reactions ◽

Ferromagnetic Phase ◽

X Ray Diffraction ◽

X Ray

Solid-state reactions between Ge and Mn films are systematically examined using X-ray diffraction, photoelectron spectroscopy and magnetic measurements. The films have a nominal atomic ratio Ge:Mn = 40:60 and are investigated at temperatures from 50 to 500 °С. It is established that after annealing at ~120 °С, the ferromagnetic Mn5Ge3 phase is the first phase to form at the 40Ge/60Mn interface. Increasing the annealing temperature to 500 °С leads to the formation of the ferromagnetic phase with a Curie temperature TC ~ 360 K and magnetization MS ~ 140-200 emu/cc at room temperature. Analysis of X-ray diffraction patterns and the photoelectron spectra suggests that the increased Curie temperature and magnetization are related to the migration of C and O atoms into the Mn5Ge3 lattice and the formation of the Nowotny phase Mn5Ge3СxOy. The initiation temperature (~120 °С) of the Mn5Ge3 phase is the same both for solid-state reactions in Ge/Mn films, as well as for phase separation in GexMn1-x diluted semiconductors. We conclude that the synthesis of the Mn5Ge3 phase is the moving force for the spinodal decomposition of the GexMn1-x diluted semiconductors.

Download Full-text

1,8-Bis(dimethylamino)naphthyl-2-ketimines: Inside vs outside protonation

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.14.273 ◽

2018 ◽

Vol 14 ◽

pp. 2940-2948 ◽

Cited By ~ 1

Author(s):

A S Antonov ◽

A F Pozharskii ◽

P M Tolstoy ◽

A Filarowski ◽

O V Khoroshilova

Keyword(s):

Hydrogen Bond ◽

Solid State ◽

Gas Phase ◽

Methoxy Group ◽

Proton Sponge ◽

Hindered Rotation ◽

Aromatic Substituent ◽

Imino Nitrogen ◽

X Ray ◽

Methoxy Groups

The structure and protonation behaviour of four ortho-arylketimines of 1,8-bis(dimethylamonio)naphthalene with a different number of methoxy groups in an aromatic substituent were investigated in solution by NMR (acetone, DMSO, MeCN), in solid state by X-ray analysis and in the gas phase by DFT calculations. Both mono- and diprotonated species were considered. It has been shown that E-isomers of neutral imines can be stabilised by an intramolecular C=N−H···OMe hydrogen bond with a neighbouring methoxy group. Electron-donating OMe groups dramatically increase the basicity of the imino nitrogen, forcing the latter to abstract a proton from the proton sponge moiety in monoprotonated forms. The participation of the out-inverted and protonated 1-NMe2 group in the Me2N−H···NH=C hydrogen bond is experimentally demonstrated. It was shown that the number and position of OMe groups in the aromatic substituents strongly affects the rate of the internal hindered rotation of the NH2 + fragment in dications.

Download Full-text

Bleaching the Record: After 200 Years, Single Crystal X-Ray Crystallography Reveals the Structure and Hydrogen-Bonding Properties of Hypochlorite and Hypobromite Ions in the Solid State

10.26434/chemrxiv.14706612 ◽

2021 ◽

Author(s):

Filip Topic ◽

Joseph Marrett ◽

Tristan Borchers ◽

Hatem M. Titi ◽

Christopher J. Barrett ◽

...

Keyword(s):

Solid State ◽

Single Crystal ◽

Gas Phase ◽

X Ray ◽

X Ray Crystallography ◽

Single Crystal Structures ◽

Hypohalous Acids ◽

Bonding Properties ◽

Insight Into

<div>We report the first single crystal structures of hypochlorite and hypobromite salts, including hydrated sodium hypochlorite - a ubiquitous bleaching and disinfection agent in use for almost 200 years. The structures represent the first characterization of fundamentally important hypochlorite and hypobromite anions in the solid state, by X-ray crystallography and are supported by Raman spectroscopy on individual crystals. The structural analysis provides insight into supramolecular chemistry of the hypohalite ions in the hydrated environment of the NaOCl<sup>.</sup>5H<sub>2</sub>O and NaOBr<sup>.</sup>5H<sub>2</sub>O solid salts, and reveals measured Cl-O and Br-O bond lengths of 1.69 A and 1.82 A, respectively, which are significantly longer than those for corresponding higher-valence oxoanions, and in agreement with the values spectroscopically determined for hypohalous acids and corresponding oxides in the gas phase.<br></div>

Download Full-text