Copper Complexes of 1,4-Dihydrazinophtalazine. Synthesis and Spectral Characterization

Micu-Semeniuc, Rodica; Semeniuc, Radu F.; Cozar, O.; David, L.

doi:10.1080/00945719809351661

Cited by 6 publications

(8 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The deviation from octahedral geometry, reflected in the cisoid [75.58(9)–105.53(10)° ( 1 ) and 78.11(9)– 102.20(10)° ( 2 )] and transoid [150.13(9)–178.24(8)° ( 1 ) and 156.62(8)–178.62(10)° ( 2 )] angles are due to the geometrical constraints imposed by the tridentate tppz ligand around the M(II) ion, the values of the bites taken by tppz being 75.58(9) and 75.73(9)° ( 1 ) and 78.11(9) and 78.66(9)° ( 2 ). The M–N and M–S distances in 1 and 2 (Table ) are unexceptional, and they well correlate with values reported for related thiocyanate-containing six-coordinate Co(II) and Ni(II) complexes. − (see Tables S3 and S4, Supporting Information).…”

Section: Resultssupporting

confidence: 77%

“…For instance, the presence of thiocyanate bridges in cobalt(II) complexes is quite unusual. A search in the CSD (Cambridge Structural Database, Version 5.34) reveals only a few thiocyanate-bridged cobalt(II) systems, and some of them are given in the reference list. − Thiocyanate-bridged nickel(II) complexes are more numerous. − Nevertheless, the examples of nickel(II) chains with single thiocyanate linkers are still limited, only 10 of such systems being reported so far. ,,− , − …”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Ferromagnetic Coupling Through the End-to-End Thiocyanate Bridge in Cobalt(II) and Nickel(II) Chains

Palion-Gazda

Machura

Lloret

et al. 2015

Crystal Growth & Design

106

View full text Add to dashboard Cite

The preparation, spectroscopic characterization, and X-ray crystal structure of two novel one-dimensional compounds of formula [MII(tppz)(NCS)(μ-1,3-NCS)] n [tppz = 2,3,5,6-tetrakis(2-pyridyl)pyrazine and M = Co(1) and Ni (2)] are reported. 1 and 2 are isomorphous compounds, and they crystallize in the P21/n space group. Their structures are made up of zigzag chains of cobalt(II) (1) and nickel(II) ions (2) bridged by single end-to-end thiocyanate groups with a tridentate tppz molecule and a terminally bound thiocyanate-N ligand achieving distorted MN5S octahedral surroundings around each metal center. The main source of the distortion of the ideal octahedron is due to the geometrical constraints issued from the occurrence of two fused five-member chelate rings of the tridentate tppz ligand, the values of the N–M–N bond angles covering the range 75.58(9)–78.66(9)°. The M–N bond lengths vary in the range 2.025(3)–2.116(29 (1) and 2.001(2)–2.079(2) Å (2), and they are shorter than the M–S bond distance [2.6395(10) (1) and 2.5225(9) Å (2)]. The values of the intrachain metal–metal separation are 6.4197(7) (1) and 6.3257(5) Å (2). The magnetic properties of 1 and 2 have been investigated in the temperature range 1.9–300 K. Both compounds exhibit intrachain ferromagnetic interactions with values of the magnetic coupling (J) of +4.60 (1) and +7.82 cm–1 (2) [the spin Hamiltonian being defined as Ĥ = −JΣ i = 1 n–1 Ŝ i Ŝ i+1].

show abstract

Section: Resultssupporting

confidence: 77%

Section: Introductionmentioning

confidence: 99%

Ferromagnetic Coupling Through the End-to-End Thiocyanate Bridge in Cobalt(II) and Nickel(II) Chains

Palion-Gazda

Machura

Lloret

et al. 2015

Crystal Growth & Design

106

View full text Add to dashboard Cite

show abstract

“…Mechanism of Isomerization. Surprisingly few examples of metal complexes of dabp have been reported, − although it remains a popular component of chiral Schiff base ligands. − Despite a report to the contrary, it is significant that in every case where diastereomers may have been expected upon complexation of dabp, only single isomers were observed. ,, We have recently synthesized [Ru(bipy) 2 (dabp)] 2+ and found only one diastereomer . It is remarkable that a square-planar Pt(II) complex of dabp has been resolved wherein the dabp ligand appears to be the only source of optical activity and that activity is not lost in solution over a period of hours .…”

Section: Discussionmentioning

confidence: 99%

Kinetics and Mechanism of the Stereochemical Isomerization of an Arene−Ruthenium Complex of the Atropisomeric Ligand 1,1‘-Biphenyl-2,2‘-diamine

1999

View full text Add to dashboard Cite

(η6-Benzene)(δ/λ-1,1‘-biphenyl-2,2‘-diamine)chlorometal(II) hexafluorophosphate (1; metal = ruthenium, osmium) have been synthesized. The rigid nature of the seven-membered chelate ring formed by the 1,1‘-biphenyl-2,2‘-diamine (dabp) ligand renders the complexes chiral. The resulting C 1 molecular symmetry of 1(M=Ru) that we have observed in the solid state by single-crystal X-ray crystallography is preserved in solution on the NMR time scale. The four N−H protons of 1(M=Ru,Os) are chemically inequivalent in the 1H NMR spectrum at 20 °C. Spin-perturbation NMR experiments in acetone solutions reveal pairwise exchange of the resonances that correspond to the N−H protons on the spin-relaxation time scale. The three mechanisms that would account for such an exchange (atropisomerization of the dabp ligand, inversion of stereochemistry at the metal center, and simultaneous inversion of the stereochemistry at the metal and the ligand) are distinguishable, provided a proper assignment of the four N−H protons can be made in the NMR spectra. Having made that assignment, we conclude from 2D EXSY NMR spectroscopy that the mechanism of exchange is inversion of stereochemistry at the dabp ligand center. This observation contrasts with previous reports that conformational isomers of dabp can be resolved.

show abstract

“…1,4-Dihydrazinophthalazine (DHPZ) sulfate possesses a wide range of applications from the well-known antihypertensive agent , to the available pharmaceutical analytical reagent , and lead complexes and new biologically active compounds − characterized by ESR, NMR, or IR spectroscopy. Efforts have been directed toward studying the influence of these DHPZ drugs on arterial pressure, cardiac rate, and urinary excretion of catecholamines at low concentrations. − …”

Section: Introductionmentioning

confidence: 99%

Surface Enhanced Raman Spectroscopy and Theoretical Studies on 1,4-Dihydrazinophthalazine Sulfate

et al. 2002

View full text Add to dashboard Cite

The two tautomeric forms of 1,4-dihydrazinophthalazine sulfate have been studied by means of density functional theory calculations. The computed structural parameters agree very well with the experimental values of the related crystal structure. The SERS spectrum of 1,4-dihydrazinophthalazine sulfate was then recorded at different solution concentrations and discussed on the basis of the SERS “surface selection rules“ in conjunction with the results of theoretical calculations. 1,4-Dihydrazinophthalazine sulfate was found to be mainly chemisorbed on the Ag colloid and to not undergo photochemistry to a photoproduct as reflected by the SERS spectra and calculations. At about 10-6 mol L-1 the molecular skeletal plane is probably oriented perpendicular to, or at least significantly tilted with respect to, the Ag surface plane. With the increase in solution concentration, a surface coverage with 1,4-dihydrazinophthalazine sulfate may occur.

show abstract

Copper Complexes of 1,4-Dihydrazinophtalazine. Synthesis and Spectral Characterization

Cited by 6 publications

References 13 publications

Ferromagnetic Coupling Through the End-to-End Thiocyanate Bridge in Cobalt(II) and Nickel(II) Chains

Ferromagnetic Coupling Through the End-to-End Thiocyanate Bridge in Cobalt(II) and Nickel(II) Chains

Kinetics and Mechanism of the Stereochemical Isomerization of an Arene−Ruthenium Complex of the Atropisomeric Ligand 1,1‘-Biphenyl-2,2‘-diamine

Surface Enhanced Raman Spectroscopy and Theoretical Studies on 1,4-Dihydrazinophthalazine Sulfate

Contact Info

Product

Resources

About