Bis(1°-amino)cyclodistib(III)azanes:  the First Structural Characterization of cis and trans Isomers of a Single Cyclodipnict(III)azane

This work presents the synthesis and characterization of a series of substituted pyridylpentafluroporphyrins, including the separation of the cis- and trans-isomers, the latter being characterized by X-ray crystallography. The spectroscopic and electrochemical properties of the series are dependent on the number of electron withdrawing pentafluorophenyl substituent, but they do not depend on the symmetry of the molecule. Ongoing from the monosubstituted to the more substituted pentafluorophenyl porphyrin H2(MPyTFPP) derivative, the Soret bands are slightly red-shifted and their quantum fluorescence yields range from 0.035 to 0.046, consistent with the value of 0.045 for the fully substituted 5,10,15,20-tetrapentafluorophenylporphyrin (dichloromethane solutions). The redox potentials of the reductive processes of monoanion and dianion formation are also sensitive to the number of pentafluoro substituents, shifting 180 mV to more positive values for the P0/P-1process ongoing from the monopentafluoro to the tris-pentafluorophenyl substituted derivative.

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Synthesis and NMR characterization of the cis and trans isomers of [Ptii(N9-adeH)2(pz)2] and X-ray crystallography of the trans isomer

Dalton Transactions ◽

10.1039/b709697f ◽

2007 ◽

pp. 3966 ◽

Cited By ~ 6

Author(s):

Karel D. Klika ◽

Henri Kivelä ◽

Vladimir V. Ovcharenko ◽

Ville Nieminen ◽

Reijo Sillanpää ◽

...

Keyword(s):

Trans Isomer ◽

Trans Isomers ◽

X Ray ◽

X Ray Crystallography ◽

Cis And Trans Isomers ◽

Nmr Characterization ◽

Cis And Trans

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ChemInform Abstract: PREPARATION AND CHARACTERIZATION OF PHOSPHETAN ALKOXIDES AND ARYLOXIDES, PRODUCTION OF CIS- AND TRANS-ISOMERS FROM TRANS-1-CHLOROPHOSPHETAN 1-OXIDE

Chemischer Informationsdienst ◽

10.1002/chin.197421308 ◽

1974 ◽

Vol 5 (21) ◽

pp. no-no

Author(s):

JOHN EMSLEY ◽

TREVOR B. MIDDLETON ◽

JOHN K. WILLIAMS

Keyword(s):

Trans Isomers ◽

Cis And Trans Isomers ◽

Cis And Trans

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Preparation and characterization of phosphetan alkoxides and aryloxides. Production of cis- and trans-isomers from trans-1-chlorophosphetan 1-oxide

Journal of the Chemical Society Dalton Transactions ◽

10.1039/dt9740000633 ◽

1974 ◽

pp. 633 ◽

Cited By ~ 7

Author(s):

John Emsley ◽

Trevor B. Middleton ◽

John K. Williams

Keyword(s):

Trans Isomers ◽

Cis And Trans Isomers ◽

Cis And Trans

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Metalloporphyrins as chemical shift reagents: the unambiguous NMR characterization of the cis- and trans-isomers of meso-(bis)-4′-pyridyl-(bis)-4′-carboxymethylphenylporphyrins

Tetrahedron ◽

10.1016/j.tet.2007.03.135 ◽

2007 ◽

Vol 63 (23) ◽

pp. 5006-5013 ◽

Cited By ~ 13

Author(s):

Teresa Gianferrara ◽

Davide Giust ◽

Ioannis Bratsos ◽

Enzo Alessio

Keyword(s):

Chemical Shift ◽

Trans Isomers ◽

Cis And Trans Isomers ◽

Nmr Characterization ◽

Shift Reagents ◽

Cis And Trans

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Synthesis and characterization of cyclam complexes of rhodium(III)

Canadian Journal of Chemistry ◽

10.1139/v70-243 ◽

1970 ◽

Vol 48 (10) ◽

pp. 1481-1491 ◽

Cited By ~ 43

Author(s):

E. J. Bounsall ◽

S. R. Koprich

Keyword(s):

Electronic Spectra ◽

Single Case ◽

Synthesis And Characterization ◽

Trans Isomers ◽

Trans Effect ◽

Linkage Isomers ◽

Cis And Trans Isomers ◽

Cyclam Complexes ◽

Cis And Trans

A series of complexes of the type Rh(cyclam)X2+ and Rh(cyclam)XYn+ have been prepared and characterized, where cyclam represents 1,4,8,11-tetraazacyclotetradecane and X and Y represent OH−, H2O, Cl−, Br−, I−, N3−, NCS−, and NO2−. The infrared and electronic spectra are discussed with respect to assignment of the cis and trans isomers, the linkage isomers, and the Rh–ligand stretching frequencies above 250 cm−1. The thermodynamic trans effect is related to shifts in the Rh–ligand stretching frequencies. The intensities of the d–d transitions are related to distortion of the octahedral field to support the cis and trans assignments, and compared to show the decrease in bond constraint for propylene linkages in place of ethylene. Steric constraint accounts for the single case of stereoisomerization by cis-Rh(cyclam)I2+.

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Mono- and dinuclear palladium complexes containing 2-pyridylphosphine ligands, including X-ray characterization of Pd2I2(µ-PPh2py)2 and a dimethylacetylenedicarboxylate A-frame complex Pd2Cl2(µ-Ppy3)2(µ-MeO2C•C=C•CO2Me); py = 2-pyridyl

Canadian Journal of Chemistry ◽

10.1139/v92-100 ◽

1992 ◽

Vol 70 (3) ◽

pp. 751-762 ◽

Cited By ~ 34

Author(s):

Yun Xie ◽

Chung-Li Lee ◽

Yeping Yang ◽

Steven J. Rettig ◽

Brian R. James

Keyword(s):

Palladium Complexes ◽

Monoclinic Space Group ◽

Trans Isomers ◽

Space Group ◽

X Ray ◽

Mononuclear Complexes ◽

Cis And Trans Isomers ◽

Pyridylphosphine Ligands ◽

Cis And Trans

Dibromo- and diiodo[(2-pyridyl)phosphine]palladium(II) complexes are prepared by metathesis of cis-PdCl2(PPh3−npyn)2 species (n = 1–3) using the appropriate sodium halide; py = 2-pyridyl. NMR spectroscopy, particularly,13C{1H}, is used to distinguish cis and trans isomers. The dinuclear complexes Pd2X2(μ-PPh3−npyn)2, X = halide, are synthesized via a conproportionation reaction using PdX2(PPh3−npyn)2 and Pd2(dba)3; dba = dibenzylideneacetone. Both Pd2l2(μ-PPh2py)2 and a dimethylacetylenedicarboxylate A-frame complex Pd2Cl2(μ-Ppy3)2(μ-MeO2C•C=C•CO2Me) are characterized crystallographically as head-to-tail isomers. The former crystallizes in the monoclinic space group C2/c with a = 30.992(3), b = 18.764(1), c = 13.100(1) Å, β = 100.676(5)°, and Z = 8; the data were refined to R = 0.035 for 5874 reflections with I ≥ 3σ(I). The A-frame compound is triclinic of space group [Formula: see text] with a = 13.545(2), b = 15.064(2), c = 11.991(2) Å, α = 111.56(1), β = 95.36(1), γ = 97.63(1)°, and Z = 2; R = 0.033 from 7128 reflections with I ≥ 3σ(I). The Pd2X2(μ-PPhpy2)2 complexes exist as a mixture of diastereomers because of chirality induced at the phosphorus atoms. The Pd2X2(μ-Ppy3)2 complexes in water generate the [Pd2(H2O)2(μ-Ppy3)2]2+ dication, which is isolated as various salts. The mononuclear complexes in water generate aquo and hydroxo species. Keywords: dimethylacetylenedicarboxylate adducts, palladium complexes (dinuclear), pyridylphosphines.

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