Reaktionsprodukte yon Oxylsäuremethylester-N-methylamiden mit Antimon(V)-chlorid. Molekülspektren und Struktur / Reaction Products of Oxalic Acid Methylester-N-methylamides and Antimony(V) Chloride. Molecular Spectra and Structure

1979 ◽  
Vol 34 (3) ◽  
pp. 398-405 ◽  
Author(s):  
M. Rössler ◽  
W. Schwarz ◽  
A. Schmidt
Keyword(s):  
Molecular Structure ◽  
Oxalic Acid ◽  
Nmr Spectra ◽  
Crystal And Molecular Structure ◽  
Molecular Spectra ◽  
Reaction Products ◽  
Addition Compound ◽  
Ring Systems ◽  
X Ray ◽  
H Nmr

Abstract Oxalic acid dimethylester and the oxalic acid methylester-N-methylamides 2 and 4, resp., react with antimony(V) chloride to yield the 1 : 1 addition compound 5 or the cyclic tetrachloroantimony(V) compounds 1, 3 and 6, resp., which represent SbO2C2 and SbONC2 five ring systems, resp. Li oxalic acid methylester-N-methylimide (9) and anti-mony(V) chloride gives the bicyclic octachloro-N-methylamido oxalato-O,O′-O,N-diantimony(V) (10). The crystal and molecular structure of tetrachloro-N-methylamino oxalato-O,O′-antimony(V) (3) is determined by X-ray analysis. The vibrational and 1H NMR spectra of 2-10 are reported and discussed.

Photoreaktionen von Dekacarbonyldirhenium mit Allen und unverzweigten Allenderivaten / Photoreactions of Decacarbonyldirhenium with Allene and Unbranched Derivatives of Allene

1995 ◽  
Vol 50 (4) ◽  
pp. 649-660 ◽  
Author(s):  
Cornelius G. Kreiter ◽  
Wolfgang Michels ◽  
Gerhard Heeb
Keyword(s):  
Nmr Spectra ◽  
Crystal And Molecular Structure ◽  
Reaction Products ◽  
X Ray Diffraction ◽  
X Ray ◽  
H Nmr ◽  
Oxidative Rearrangement ◽  
Dirhenium Complexes ◽  
Derivatives Of ◽  
By Products

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.

The Meisenheimer Rearrangement in Heterocyclic Synthesis. IV. Derivatives of the 2H,6H-1,5,4-Benzodioxazocine and 7H-1,6,5-Benzodioxazonine Ring Systems: X-Ray Crystal Structure of 10-Methoxy-5-methyl-7-phenyl-2,3,4,5-tetrahydro-7H-1,6,5-benzodioxazonine

1988 ◽  
Vol 41 (3) ◽  
pp. 293 ◽  
Author(s):  
JB Bremner ◽  
EJ Browne ◽  
LM Engelhardt ◽  
IWK Gunawardana ◽  
AH White
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Crystal And Molecular Structure ◽  
Ring System ◽  
Heterocyclic Synthesis ◽  
Rearrangement Product ◽  
Ring Systems ◽  
X Ray ◽  
Derivatives Of ◽  
Moderate Yield

Meisenheimer rearrangement of the N-oxides (4) derived from a series of 5-aryl-4-methyl-2,3,4,5-tetrahydro-1,4-benzoxazepines (3) gave rise to eight derivatives (5) of the new 2H,6H-1,5,4-benzodioxazocine ring system. Reaction of 9-methoxy-5-methyl-6-phenyl-3,4,5,6- tetrahydro-2H-1,5-benzoxazocine (6) with 3-chloroperoxybenzoic acid gave an unstable N-oxide (7). A Meisenheimer rearrangement product from (7), 10-methoxy-5-methyl-7-phenyl-2,3,4,5-tetrahydro-7 H-1,6,5- benzodioxazonine (8), the first example of this ring system, was isolated directly in moderate yield on oxidation of (6) with cooling. The crystal and molecular structure of (8) has been determined by X-ray crystallographic methods.

Synthesis and Electrochemistry of Aluminum Porphycenes: Crystal and Molecular Structure of Methyl-σ-Bonded Aluminum Etioporphycene

1997 ◽  
Vol 01 (02) ◽  
pp. 109-119 ◽  
Author(s):  
ROGER GUILARD ◽  
VIRGINIE PICHON-PESME ◽  
HASSANE LACHEKAR ◽  
CLAUDE LECOMTE ◽  
ALLY M. AUKAULOO ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Crystal And Molecular Structure ◽  
Structural Data ◽  
Synthesis And Characterization ◽  
X Ray Diffraction ◽  
X Ray ◽  
H Nmr ◽  
Axial Ligands ◽  
Uv Visible

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.

On the Stereoselectivity of the (-)-Dimenthyl Malonate Addition to α,β-Unsaturated Ketones

1996 ◽  
Vol 61 (12) ◽  
pp. 1805-1814 ◽  
Author(s):  
Ľubomír Šebo ◽  
Juraj Alföldi ◽  
Grety Rihs ◽  
Štefan Toma
Keyword(s):  
Michael Addition ◽  
Pure State ◽  
Nmr Spectra ◽  
Reaction Products ◽  
X Ray ◽  
Unsaturated Ketones ◽  
H Nmr ◽  
The Michael Addition

The Michael addition of (-)-dimenthyl malonate to eight α,β-unsaturated ketones has been studied. The ratio of diastereomers was calculated on the basis of the 1H NMR spectra of the crude reaction products. The diastereomer excess varied from 10 to 50%, depending on the structure of the starting enone. The pure diastereomer produced by addition of (-)-dimenthyl malonate to 2-benzylidene-1,4-indandione was isolated by repeated crystallization. X-ray analysis has shown that the isomer is (-)-dimenthyl (R)-2-[1-(1,3-dioxoindan-2-yl)-1-phenylmethyl]malonate (5a). The predominating diastereomers of (-)-dimenthyl(3-ferrocenyl-3-oxophenylpropyl)malonate (1a) and (-)-dimenthyl-2-(1-(1,3-dioxo[3]ferrocenophan-2-yl)-1-phenyl malonate (6a) were also isolated in pure state by careful crystallization.

Nitrones and oximes of bifunctional carbonyl compounds and their reaction products with diarylborinic acids. Crystal and molecular structure of examples of five-, six-, and seven-membered boron chelates

2000 ◽  
Vol 78 (10) ◽  
pp. 1325-1344
Author(s):  
Wolfgang Kliegel ◽  
Gottfried Lubkowitz ◽  
Jens O Pokriefke ◽  
Steven J Rettig ◽  
James Trotter
Keyword(s):  
Molecular Structure ◽  
Carbonyl Compounds ◽  
Spectroscopic Data ◽  
Crystal And Molecular Structure ◽  
Direct Methods ◽  
Reaction Products ◽  
Boron Chelates ◽  
Full Matrix ◽  
Space Group ◽  
X Ray

Synthesis has been carried out of diarylboron chelates of 2- and 3-hydroxynitrones, of 2- and 3-hydroxyoximes, and of 2-carboxynitrones and a 2-carboxyoxime. The structures have been determined from spectroscopic data and from X-ray analyses of 5d, 9a, 11b, and 19. Crystals (at 180 K) of 5d are monoclinic, a = 10.543(2), b = 19.085(4), c = 10.2667(3) Å, β = 90.4978(7)°, Z = 4, space group P21/c; those of 9a are orthorhombic, a = 10.9913(5), b = 14.9329(7), c = 10.2460(13) Å, Z = 4, space group P212121; those of 11b are monoclinic, a = 11.227(2), b = 9.967(2), c = 17.0537(4) Å, β = 105.4179(5)°, Z = 4, space group P21/n; those of 19 are monoclinic, a = 11.1847(15), b = 13.715(3), c = 11.5559(5) Å, β = 104.8730(10)°, Z = 4, space group P21/n. The structures were solved by direct methods and refined by full-matrix least-squares procedures to R(F, I [Formula: see text] 3σ(I)) = 0.049, 0.047, 0.042, and 0.047, respectively, for CCD data for 5d, 9a, 11b, and 19. The four molecules contain five-, seven-, six-, and five-membered rings, respectively, with O-B-N groups in the 5d, 11b, and 19, and O-B-O in 9a; the rings exhibit various deviations from planarity, particularly the seven-membered ring.Key words: diarylboron chelates, hydroxyoximes, hydroxynitrones, carboxyoximes, carboxynitrones, organoboron compounds, crystal structure.

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
Keyword(s):  
Molecular Structure ◽  
Crystal And Molecular Structure ◽  
Prototropic Tautomerism ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
X Ray ◽  
H Nmr ◽  
Compound C ◽  
Crystallographic Symmetry ◽  
Derivatives Of

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.

Coordination Behavior of tBu2PH towards [{Rh(μ-Cl)(coe)2}2] (coe = cis-cyclooctene): Crystal and Molecular Structure of [{Rh(μ-Cl)(tBu2PH)2}2]

2008 ◽  
Vol 63 (9) ◽  
pp. 1035-1039 ◽  
Author(s):  
Hans-Christian Böttcher ◽  
Peter Mayer
Keyword(s):  
Molecular Structure ◽  
Nmr Spectroscopy ◽  
Crystal And Molecular Structure ◽  
Molar Ratio ◽  
X Ray ◽  
X Ray Crystallography ◽  
Molar Ratios ◽  
H Nmr ◽  
Coordination Behavior ◽  
Independent Synthesis

The reaction of [{Rh(μ-Cl)(coe)2}2] (coe = cis-cyclooctene) with tBu2PH in different solvents in various molar ratios was investigated. Working with a molar ratio of Rh to P = 1 : 2 in heptane overnight afforded [{Rh(μ-Cl)(tBu2PH)2}2] (1) in nearly quantitative yield. Upon tuning the molar ratio (Rh/P) in the range from 1 : 2 to 1 : 0.5, 31P{1H} NMR spectroscopy indicated the formation of [(tBu2PH)2Rh(μ-Cl)2Rh(coe)2] (3) besides the complexes [{Rh(μ-Cl)(coe)(tBu2PH)}2] (cis, 2a; trans, 2b). The constitution of 3 was established by an independent synthesis mixing 1 with [{Rh(μ- Cl)(coe)2}2] or [{Rh(μ-Cl)(cod)}2] (cod = 1.4-cyclooctadiene), respectively, which also yielded [(tBu2PH)2Rh(μ-Cl)2Rh(cod)] (4). Single crystals of 1 have been analyzed by X-ray crystallography (monoclinic, Cc, Z = 8, a = 32.7375(3), b = 11.1294(1), c = 24.5134(3)Å ; β = 106.7228(4)◦; V = 8553.70(15) Å3; T = 200 (2) K).

Sterically Crowded Heterocycles. I. Molecular Structure of 3-Chain Substituted 2-Phenylimidazo[1,2-a]pyridinium Salts

1994 ◽  
Vol 59 (12) ◽  
pp. 2677-2690 ◽  
Author(s):  
Stanislav Böhm ◽  
Richard Kubík ◽  
Martin Hradilek ◽  
Jan Němeček ◽  
Michal Hušák ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Nmr Spectra ◽  
Molecular Structures ◽  
Pyridinium Salts ◽  
Protonation Site ◽  
X Ray ◽  
H Nmr ◽  
C Nmr ◽  
Pyridinium Perchlorate

2-Phenyl-3-[(Z)-1,3-diphenyl-3-oxopropenyl]imidazo[1,2-a]pyridine (I) was converted to corresponding 1-alkyl-2-phenyl-3-[(Z)-1,3-diphenyl-3-oxopropenyl]imidazo[1,2-a]pyridinium salts III - VI and 2-phenyl- 3-[(Z)-1,3-diphenyl-3-oxopropenyl]imidazo[1,2-a]pyridinium perchlorate (VII). The protonation site is discussed in terms of calculated molecular energies of alternative cations. The X-ray structure analyses of enone I and its quaternary periodide III are reported and compared with the PM3 molecular optimizations. 1H NMR and 13C NMR spectra reveal well changes of molecular structures caused by the transformation of the base I into salts III - VII.

Complexes of dodecamethylcyclohexaphosphazene with palladium(II) chloride and platinum(II) chloride. Crystal and molecular structure of cis-dichloro[η2-dodecamethylcyclohexaphosphazene (N,N′)] palladium(II) sesquihydrate

1981 ◽  
Vol 59 (16) ◽  
pp. 2429-2434 ◽  
Author(s):  
Norman L. Paddock ◽  
T. N. Ranganathan ◽  
Steven J. Rettig ◽  
Rajendra D. Sharma ◽  
James Trotter
Keyword(s):  
Molecular Structure ◽  
Bond Order ◽  
Nmr Spectra ◽  
Crystal And Molecular Structure ◽  
Model Calculations ◽  
Full Matrix ◽  
X Ray ◽  
Square Planar ◽  
The Mean ◽  
C Nmr

Dodecamethylcyclohexaphosphazene N6P6Me12, 1, forms 1:1 complexes with palladium(II) chloride, 2, and platinum(II) chloride, 3. Their 31P, 1H, and 13C nmr spectra show them to be rigid molecules in solution, with an approximate plane of symmetry. Crystals of 2 are orthorhombic, a = 17.4030(3), b = 15.4897(5), c = 10.7417(2) Å, Z = 4, space group P21212. The structure was determined from diffractometer X-ray data and refined by full-matrix least-squares methods to R = 0.031 for 3545 reflections with I ≥ 3σ(I). The metal atom has square planar coordination, and forms 6- and 10-membered chelate rings with the phosphazene ligand. The mean P—N bond length is 1.609 Å; the variation of bond lengths within the ring is consistent with model calculations of changes in bond order arising from the localization of bonding electrons.

Gehinderte Ligandbewegungen in Übergangsmetallkomplexen, XXVIII [1] Photochemische C–H-Aktivierung an 1,3,5-Cycloheptatrien durch Rhenium(O) / Hindered Ligand Movements in Transition Metal Complexes, XXVIII [1] Photochemical C–H-Activation at 1,3,5-Cycloheptatriene by Rhenium(O)

1985 ◽  
Vol 40 (9) ◽  
pp. 1188-1198 ◽  
Author(s):  
Cornelius G. Kreiter ◽  
Karl Heinz Franzreb ◽  
Wolfgang Michels ◽  
Ulrich Schubert ◽  
Klaus Ackermann
Keyword(s):  
Molecular Structure ◽  
Transition Metal ◽  
Transition Metal Complexes ◽  
Nmr Spectra ◽  
Thermal Reaction ◽  
Stable Isomer ◽  
Temperature Dependent ◽  
Activation Barriers ◽  
X Ray ◽  
H Nmr

Decacarbonyl-dirhenium(O) (1) photochemically cleaves C-H-bonds in 1,3,5-cycloheptatriene (2 ) and forms two isomeric Re2(CO)8(μ-H)(μ-η2:1-cycloheptatrienyl) complexes (3, 4). In addition Re(CO)3(η5-cycloheptatrienyl) (5) and Re(CO)3(η5-cycloheptadienyl) (6) are obtained. The complexes 3 and 4 show temperature dependent 1H NMR spectra due to hindered ligand movements of the cycloheptatrienyl bridges with activation barriers of ⊿G≠207 = 39.9±2 kJ mol-1 and ⊿G≠255 = 48.0±2 kJ mol-1. 3 and 4 achieve in a thermal reaction an equilibrium with populations of 0.03 and 0.97 at 350 K with ⊿G≠350 - 96.5±5 kJ mol-1. The molecular structure of the more stable isomer, Re2(CO)8(μ-H)(μ-η2:1-1 ,3,5-cycloheptatrien-2-yl) (4 ) was determined by X-ray structure analysis.

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