Derivatives of the Triaminoguanidinium Ion, 2. Prototropic Tautomerism, Crystal and Molecular Structure of N,N´,N´´-Tris(propan- 2-iminyl)guanidine [1, 2]

2013 ◽  
Vol 68 (3) ◽  
pp. 207-213 ◽  
Author(s):  
Jan Szabo ◽  
Gerhard Maas

The title compound, C10H20N6 (2), was prepared from N,N´,N´´-triaminoguanidinium chloride. Solvent- and temperature-dependent 1H NMR spectra indicating prototropic tautomerism were observed in solution. The crystal and molecular structure was determined by X-ray diffraction analysis. The compound crystallizes in the hexagonal space group P63/m. The molecules lie on crystallographic mirror planes parallel to the a,b plane, which are separated from each other by 3:37 Å . The threefold crystallographic symmetry of the molecules is due to disorder with positional averaging of individual molecules.

1995 ◽  
Vol 50 (4) ◽  
pp. 649-660 ◽  
Author(s):  
Cornelius G. Kreiter ◽  
Wolfgang Michels ◽  
Gerhard Heeb

Decacarbonyldirhenium (1) reacts upon UV irradiation with allene (2), 1,2-butadiene (3) and 2,3-pentadiene (4) preferentially by CO substitution and oxidative rearrangement to the corresponding enneacarbonyl-μ-η1:3-endiyl-dirhenium complexes 5, 9, and 15 and to the octacarbonyl-μ-η2:2-allene-dirhenium complexes 6, the stereoisomers 10, 11, and 16. At elevated temperature 5, 9, and 15 loose CO and yield by a reductive rearrangement also the complexes 6, 10, 11, and 16. In addition to these main products, depending upon the allene derivative used, various by-products are obtained.By-products of the reaction o f 1 with 2 are octacarbonyl-μ-η3:3-(2,3-dimethylene-buta-1,4- diyl)dirhenium (7) and μ-η2:2-allene-hexacarbonyl-μ-η1:3-1-propene-1,3-diyl-dirheniurn (8). The photo reaction of 1 with 3 yields, in addition to 9-11, tetracarbonyl-η3-(E-5-ethylidene- 4-methyl-2-cyclopenten-1-yl)rhenium (12) and tetracarbonyl-η3-(Z-5-ethyliden-4- methyl-2-cyclopenten-1-yl)rhenium (13) as a mixture of isomers. 1 and 4 form the by-products tetracarbonyl-η3-(EZ-3-penten-2-yl)rhenium (17), tetracarbonyl-η3-(EE-3-penten-2-yl)rhenium (18) and heptacarbonyl-μ-η1:2:1:2-(4,5-dimethyl-2,6-octadiene-3,6-diyl)dirhenium (19) with an unusually bridging and chelating ligand. The constitutions of the reaction products have been concluded from the IR and 1H NMR spectra. For 19 the crystal and molecular structure has been determined by X-ray diffraction analysis.


Author(s):  
ROGER GUILARD ◽  
VIRGINIE PICHON-PESME ◽  
HASSANE LACHEKAR ◽  
CLAUDE LECOMTE ◽  
ALLY M. AUKAULOO ◽  
...  

The synthesis and characterization of three monomeric aluminum porphycenes with anionic or σ-bonded axial ligands is reported. The investigated compounds are represented as ( EtioPc ) Al ( CH 3) and ( EtioPc ) AlX where EtioPc represents the dianion of etioporphycene and X = Cl − or OH −. Each synthesized complex was characterized by mass spectrometry. 1 H NMR, IR and UV-visible spectroscopies as well as by electrochemistry. Comparisons are made between the properties of complexes in the aluminum etioporphycene series and related chloro- or methyl σ-bonded Al ( III ) porphyrins containing octaethylporphyrin ( OEP ) or tetraphenylporphyrin ( TPP ) macrocycles. Comparisons are also made between the currently investigated compounds and a previously reported Al ( III ) μ-oxo dimer, [( EtioPc ) Al ]2 O . In addition, the crystal and molecular structure of ( EtioPc ) Al ( CH 3) was determined by X-ray diffraction. The molecular structure of this methyl-σ-bonded aluminum etioporphycene provides the first structural data for an aluminum porphycene compound. The aluminum(III) atom in ( EtioPc ) Al ( CH 3) is pentacoordinated and is located 0.54 Å from the plane of the four N -nitrogens.


ChemInform ◽  
2010 ◽  
Vol 22 (37) ◽  
pp. no-no
Author(s):  
U. FOLLI ◽  
D. IAROSSI ◽  
A. MUCCI ◽  
A. MUSATTI ◽  
M. NARDELLI ◽  
...  

1991 ◽  
Vol 246 (1-2) ◽  
pp. 99-111 ◽  
Author(s):  
Ugo Folli ◽  
Dario Iarossi ◽  
Adele Mucci ◽  
Amos Musatti ◽  
Mario Nardelli ◽  
...  

2000 ◽  
Vol 57 (1) ◽  
pp. o85-o86 ◽  
Author(s):  
Jarmila Duskova ◽  
Jiri Labsky ◽  
Jindrich Hasek ◽  
Ivana Cisarova

The crystal and molecular structure of the title compound, C11H18NO3, has been determined from X-ray diffraction data. The compound crystallizes in the centrosymmetric space groupPnma. The main part of the molecule lies at a special position on the mirror plane.


1983 ◽  
Vol 61 (7) ◽  
pp. 1603-1607 ◽  
Author(s):  
Kathy A. Beveridge ◽  
Gordon W. Bushnell ◽  
Reginald H. Mitchell

Conformations in a variety of cyclophane structures are discussed, as determined by X-ray diffraction in crystals and by 1Hmr in solution. Established nomenclature is brought forward (syn/anti and synclinal/anticlinal) and used to deal with an intermediate case which has been examined by both techniques. The crystal and molecular structure of the title compound, C16H16S4, is determined and refined to R = 0.0497. The crystal is orthorhombic, space group Pbca, a = 16.593(2), b = 10.018(2), c = 19.407(3) Å at 25(2) °C, Z = 8, Dcalc = 1.386 g cm−3. The molecular conformation in the crystal is anticlinal with a dihedral angle between the benzene rings of 101°. The benzene rings are displaced laterally by 0.727 Å and the sequence of torsion angles is similar in the two bridging chains.


1996 ◽  
Vol 51 (6) ◽  
pp. 832-837 ◽  
Author(s):  
Konstantin V. Domasevitch ◽  
Victor V. Skopenko ◽  
Eduard B. Rusanov

Abstract Diphenyltellurium(IV) derivatives of the types Ph2Te{ACO}2 (1), Ph4Te2O{ACO}2 (2) and Ph6Te3O2{ACO} (3) (ACO = nitrosocarbamylcyanmethanide -ONC(CN)C(O)NH2) have been prepared. The IR spectroscopic data reveal that the ambidentate ligands are coordinated to the tellurium(IV) atom in a monodentate manner via the nitroso oxygen atom. The crystal and molecular structure of 3 has been determined from X-ray diffraction data (triclinic, space group P1̅ with a = 12.382(2), 6=13.100(2), c = 14.944(3) Å, a = 87.74( 1), β = 85.04(2), 7 = 66.29( 1)°, V = 2211.0 A , Z = 2, R = 0.040). The structure is made up of unsymmetric molecules, in which the tellurium atoms are linked by oxo bridges to form chains Te-O-Te-O-Te (d(Te-O) ca. 1.94-2.09 A). The Te-0 (nitroso group) bond lengths are in the range 2.33 - 2.36 Å


2011 ◽  
Vol 34 (5-6) ◽  
pp. 127-130 ◽  
Author(s):  
Yaya Sow ◽  
Libasse Diop ◽  
Kieran C. Molloy ◽  
Gabrielle Kociok-Köhn

Abstract The title compounds [R2NH2][C2O4SnMe3](R=i-Bu, Cy), in which tin atoms adopt a distorted trigonal bipyramidal configuration, have been prepared and submitted to an X-ray diffraction study. These compounds have been obtained from the reaction of (Cy2NH2)2C2O4·H2O or (i-Bu2NH2)2C2O4 with SnMe3Cl. In both [R2NH2][C2O4SnMe3] compounds, the trans complex has an almost regular trigonal bipyramidal geometry around the tin atom. The SnMe3 residues are connected as a chain with bridging oxalate anions in a trans-SnC3O2 framework, the oxygen atoms being in axial positions. The cations connect linear adjacent chains through NH…O hydrogen bonds giving layered structures.


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