On the Reaction of ortho-Diphenoquinone Valence Isomers with Primary and Secondary Amines. X-Ray Structure Analysis of a 2,3-Dihydro-1H-azepinone and its Photochemical and Oxidative Conversion Products

1979 ◽  
Vol 32 (9) ◽  
pp. 1931 ◽  
Author(s):  
H Becker ◽  
K Gustafsson ◽  
CL Raston ◽  
AH White
Keyword(s):  
Single Crystal ◽  
Secondary Amines ◽  
Reaction Products ◽  
Oxidative Conversion ◽  
X Ray Diffraction ◽  
X Ray ◽  
Primary And Secondary Amines ◽  
Diffraction Structure ◽  
Structure Determinations ◽  
Photochemical Isomerization

Single-crystal X-ray diffraction structure determinations are reported for three reaction products and photoisomers formed from reactions between an o-diphenoquinone valence isomer and primary and secondary amines, namely: 3,5-di-t-butyl-7-(3,5-di-t-butyl-2-hydroxyphenyl)-1-methyl-2,3-dihydro-1H-azepin-2-one (8; R1 = R2 = But, R3 = Me), its photochemical isomerization product 4,6-di-t-butyl-1-(3,5-di-t-butyl-2-hydroxyphenyl)-2-methyl-2-azabicyclo[3,2,0]hept-6-en-3-one (9; R1 = R2 = But, R3 = Me) and 4',5,7-tri-t-butyl-3'-(2,2-dimethylpropionyl)-1'-methylspiro[benzofuran-3(2H)-2'- pyrrolidinel-2,5'-dione (12; R1 = R2 = But, R3 = Me).

scholarly journals Synthesis of Boronated Amidines by Addition of Amines to Nitrilium Derivative of Cobalt Bis(Dicarbollide)

Molecules ◽  
2021 ◽  
Vol 26 (21) ◽  
pp. 6544
Author(s):  
Ekaterina V. Bogdanova ◽  
Marina Yu. Stogniy ◽  
Kyrill Yu. Suponitsky ◽  
Igor B. Sivaev ◽  
Vladimir I. Bregadze
Keyword(s):  
Single Crystal ◽  
Nucleophilic Addition ◽  
Triple Bond ◽  
Molecular Structures ◽  
Secondary Amines ◽  
Primary Amines ◽  
X Ray Diffraction ◽  
X Ray ◽  
Primary And Secondary Amines ◽  
E And Z Isomers

A series of novel cobalt bis(dicarbollide) based amidines were synthesized by the nucleophilic addition of primary and secondary amines to highly activated B-N+≡C–R triple bond of the propionitrilium derivative [8-EtC≡N-3,3′-Co(1,2-C2B9H10)(1′,2′-C2B9H11)]. The reactions with primary amines result in the formation of mixtures of E and Z isomers of amidines, whereas the reactions with secondary amines lead selectively to the E-isomers. The crystal molecular structures of E-[8-EtC(NMe2)=HN-3,3′-Co(1,2-C2B9H10)(1′,2′-C2B9H11)], E-[8-EtC(NEt2)=HN-3,3′-Co(1,2- C2B9H10)(1′,2′-C2B9H11)] and E-[8-EtC(NC5H10)=HN-3,3′-Co(1,2-C2B9H10)(1′,2′-C2B9H11)] were determined by single crystal X-ray diffraction.

Molecular tapes in the structure of isoguaninium chloride

2017 ◽  
Vol 74 (1) ◽  
pp. 108-112 ◽  
Author(s):  
Urszula Anna Budniak ◽  
Paulina Maria Dominiak
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Charge Density ◽  
Interaction Energy ◽  
Electrostatic Interaction ◽  
Electrostatic Interactions ◽  
The Other ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diffraction Structure

Isoguanine, an analogue of guanine, is of intrinsic interest as a noncanonical nucleobase. The crystal structure of isoguaninium chloride (systematic name: 6-amino-2-oxo-1H,7H-purin-3-ium chloride), C5H6N5O+·Cl−, has been determined by single-crystal X-ray diffraction. Structure analysis was supported by electrostatic interaction energy (E es) calculations based on charge density reconstructed with the UBDB databank. In the structure, two kinds of molecular tapes are observed, one parallel to (010) and the other parallel to (50\overline{4}). The tapes are formed by dimers of isoguaninium cations interacting with chloride anions. E es analysis indicates that cations in one kind of tape are oriented so as to minimize repulsive electrostatic interactions.

Photochemical cis-trans Isomerization of 2-Substituted 9-(2-Nitroethenyl)anthracenes. X-Ray Structure Analyses of (E)- and (Z)-9-(2-Nitro-2-phenylethenyl)anthracene

1989 ◽  
Vol 42 (4) ◽  
pp. 593 ◽  
Author(s):  
HD Becker ◽  
BW Skelton ◽  
H Sorensen ◽  
AH White
Keyword(s):  
Single Crystal ◽  
Quantum Yields ◽  
X Ray Diffraction ◽  
X Ray ◽  
Photostationary State ◽  
Trans Isomerization ◽  
Photochemical Isomerization

(E)-9-(2-Nitropropeny1)anthracene and (E)-9-(2-nitro-2-phenylethenyl)anthracene have been prepared by piperidine-catalysed condensation of 9-anthraldehyde with nitroethane and nitro(phenyl)methane, respectively. The corresponding (Z)-compounds were obtained by photochemical isomerization, quantum yields of geometrical isomerlzation being measured in cyclohexane, benzene, dichloromethane and ethanol. In virtually all solvents the (Z)-isomers are favoured at the photostationary state. The structures of (E)- and (2)-942- nitro-2-phenylethenyl)anthracene have been established by single-crystal X-ray diffraction studies.

Crystal structures of some eriostyl/nitrobenzoate derivatives

1980 ◽  
Vol 33 (2) ◽  
pp. 313 ◽  
Author(s):  
PR Jefferies ◽  
BW Skelton ◽  
B Walter ◽  
AH White
Keyword(s):  
Charge Transfer ◽  
Solid State ◽  
Single Crystal ◽  
Crystal Structures ◽  
X Ray Diffraction ◽  
X Ray ◽  
Structure Determinations

Following the suggestion made earlier, on the basis of solution spectroscopy, that a number of eriostyl/nitrobenzoate compounds form charge-transfer self-complexes, a number of these have been investigated structurally by single-crystal X-ray diffraction methods in order to ascertain the presence or otherwise of such interactions in the solid state. The substances thus studied were eriostyl 3,5-dinitrobenzoate (1), eriostyl p-nitrobenzoate (2), tetrahydroeriostyl 3,5-dinitrobenzoate (3), and eriostemyl 3,5-dinitrobenzoate (4);* structure determinations in all cases, although displaying the presence of strong charge-transfer interactions from the two moieties of each molecule, show that the interactions in the solid state are intermolecular in nature.

Chemistry of Polyhalogenated Nitrobutadienes, Part 9: Acyclic and Heterocyclic Nitroenamines and Nitroimines from 2-Nitroperchlorobuta-1,3-diene

2010 ◽  
Vol 65 (7) ◽  
pp. 843-860 ◽  
Author(s):  
Viktor A. Zapol’skii ◽  
Jan C. Namyslo ◽  
Mimoza Gjikaj ◽  
Dieter E. Kaufmann
Keyword(s):  
Single Crystal ◽  
Diffraction Analysis ◽  
Ring Closure ◽  
Reaction Products ◽  
X Ray Diffraction ◽  
Substitution Pattern ◽  
X Ray

Various amino, diamino, aminothio, or benzotriazolo compounds derived from the exceedingly versatile 2-nitroperchlorobutadiene (1) gave structurally interesting and physiologically promising nitro-enamines, -imines, -amidines, and hydrazines as well as ring closure reaction products, e. g. pyrimidines and pyrazoles. Most of these reactions turned out to be highly selective with good to very good yields. The structure of the pyrazole precursor (E,E)-1-(benzotriazol-1-yl)-4,4-dichloro-3- (4-ethoxyphenylamino)-1-(4-ethoxyphenylimino)-2-nitrobut-2-ene (30), due to its exceptional substitution pattern, was evidenced by single-crystal X-ray diffraction analysis.

Lewis-Base Adducts of Group 11 Metal(I) Compounds. LIX. Crystal Structure Determinations of Tetrakis(trimethylphosphine)copper(I) Halides and Tetrakis(triphenylphosphine)-copper(I) and -silver(I) Hexafluorophosphates

1990 ◽  
Vol 43 (10) ◽  
pp. 1697 ◽  
Author(s):  
GA Bowmaker ◽  
PC Healy ◽  
LM Engelhardt ◽  
JD Kildea ◽  
BW Skelton ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Crystal Structures ◽  
Lewis Base ◽  
X Ray Diffraction ◽  
Coordination Environment ◽  
X Ray ◽  
Bond Lengths ◽  
Cu Complex ◽  
Structure Determinations

The crystal structures of [Cu(Pme3)4]X (X = Cl , Br, I) and of [M(PPh3)4] [PF6] (M = Cu, Ag) have been determined by single-crystal X-ray diffraction methods at 295 K. The former compounds contain nearly tetrahedral [Cu(PMe3)4]+ ions on sites of m symmetry with mean Cu-P bond lengths of 2.270, 2.271 and 2.278 Ǻ for X = Cl , Br and I respectively. The latter compounds contain [M(PPh3)4]+ ions on sites of 3 symmetry. In the M =Ag complex the coordination environment is close to tetrahedral, but in the M =Cu complex the length of the axial Cu-P bond [2.465(2)Ǻ] is significantly shorter than that of the off-axis bonds [2.566(2)Ǻ]. Possible reasons for this are discussed.

Structure, Stereochemistry and Novel 'Hydrogen Bonding' in Two Bipyridinium Salts of the B10H102- Anion

1987 ◽  
Vol 40 (12) ◽  
pp. 2097 ◽  
Author(s):  
DJ Fuller ◽  
DL Kepert ◽  
BW Skelton ◽  
AH White
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonding ◽  
Charge Transfer ◽  
Single Crystal ◽  
X Ray Diffraction ◽  
Hydrogen Atoms ◽  
Full Matrix ◽  
X Ray ◽  
Structure Determinations ◽  
Positively Charged

Crystal structure determinations of (LH)2(B10H10), (1), and (LH2)(B10H10), (2), L = 2,2'- bipyridine , have been carried out by single-crystal X-ray diffraction methods at 295 K, being refined by full-matrix least squares to residuals of 0.041, 0.047 for 1758, 1771 'observed' independent reflections respectively. Crystals of (1) are monoclinic, P21/n, a 12.040(7), b 17.71(1), c 11.142(4) �, β 101.78(4)�, Z 4. Crystals of (2) are monoclinic, P21/c, a 9.937(4), b 10.837(3), c 14.856(5) �, β 109 2l(3)�, Z 4. The colour of the compounds is accounted for by charge-transfer interactions of a novel type, namely between the positively charged cationic acid hydrogen atoms and the negatively charged non-apical hydrogen atoms of the anion. In yellow (1), these distances are 2.26(5) �, while in red (2), they are much shorter, being 1.89(4), 1.97(3) �.

scholarly journals Crystal structures of cristobalite-type and coesite-type PON redetermined on the basis of single-crystal X-ray diffraction data

2015 ◽  
Vol 71 (11) ◽  
pp. 1325-1327 ◽  
Author(s):  
Maxim Bykov ◽  
Elena Bykova ◽  
Vadim Dyadkin ◽  
Dominik Baumann ◽  
Wolfgang Schnick ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Single Crystals ◽  
Crystal Structures ◽  
Rotation Axis ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
X Ray ◽  
Structure Determinations ◽  
Anisotropic Displacement Parameters

Hitherto, phosphorus oxonitride (PON) could not be obtained in the form of single crystals and only powder diffraction experiments were feasible for structure studies. In the present work we have synthesized two polymorphs of phosphorus oxonitride, cristobalite-type (cri-PON) and coesite-type (coe-PON), in the form of single crystals and reinvestigated their crystal structures by means of in house and synchrotron single-crystal X-ray diffraction. The crystal structures ofcri-PON andcoe-PON are built from PO2N2tetrahedral units, each with a statistical distribution of oxygen and nitrogen atoms. The crystal structure of thecoe-PON phase has the space groupC2/cwith seven atomic sites in the asymmetric unit [two P and three (N,O) sites on general positions, one (N,O) site on an inversion centre and one (N,O) site on a twofold rotation axis], while thecri-PON phase possesses tetragonalI-42dsymmetry with two independent atoms in the asymmetric unit [the P atom on a fourfold inversion axis and the (N,O) site on a twofold rotation axis]. In comparison with previous structure determinations from powder data, all atoms were refined with anisotropic displacement parameters, leading to higher precision in terms of bond lengths and angles.

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