Synthesis and the reversed-phase HPLC analysis ofcis andtrans-dichlorobis(ethylenediamine-ruthenium) chloride isomers

Gonçalves, N. S.; Vasconcellos, L. C. G.; Mazzetto, Selma Elaine

doi:10.1007/bf02492557

Cited by 2 publications

(1 citation statement)

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“…23 The UV-Vis spectrum of an aqueous solution of in clusion compound 1 is, on the whole, similar to the spec trum of the "free" complex trans [Ru(en) 2 Cl 2 ]Cl. [36][37][38] In the UV-Vis spectra, the charge transfer bands e g * ←e u from the occupied p-π orbital of the chloride ligand to the unoccupied d orbital of ruthenium are the major bands. The inclusion of the trans [Ru(en) 2 Cl 2 ] + cation into CB [8] leads to a substantial bathochromic shift of the most intense absorption band of the complex at 343 nm (to 352 nm for 1) and an increase in the extinction coef ficient of this band.…”

Section: Resultsmentioning

confidence: 99%

Inclusion compounds of cucurbit[8]uril with noble metal polyamine complexes

et al. 2010

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Inclusion compounds of the macrocyclic cavitand cucurbit[8]uril (CB[8]) with the ruthenium(III) bis(ethylenediamine) complex {trans [Ru(en) 2 Cl 2 ]@CB[8]}Cl•27.5H 2 O (1), the gold(III) diethylenetriamine complex {[Au(dien)Cl]@CB[8]}Cl 2 •11H 2 O (2), and the gold(III) and platinum(II) cyclam complexes (H 3 O) 5 {[Au(cyclam)]@CB[8]}Cl 8 •18H 2 O (3) and {[Pt(cyclam)] 0.11 (H 2 cyclam) 0.89 @CB[8]}Cl 2 •16H 2 O (4), respectively, where cyclam is the tetra azamacrocyclic ligand, were synthesized. The inclusion compounds were synthesized both directly starting from CB[8] and the metal complexes with polyamines (en or dien) and by the two step method with the use of the cyclic polyamine ligand (cyclam) pre included into the cavity of the macrocycle. The inclusion compounds were characterized by X ray diffraction (1, 2, and 4), IR spectroscopy, electrospray ionization mass spectrometry, UV-Vis spectro scopy, and thermogravimetric analysis.Cucurbit[n]urils (C 6n H 6n N 4n O 2n , CB[n]; n = 5-10) comprise a family of macrocyclic molecules containing an open hydrophobic intramolecular cavity accessible through two hydrophilic portals formed by n carbonyl groups. 1-4 This structure determines the behavior of cucurbit[n]urils as cavitands, viz., host molecules capable of encapsulating guest molecules of suitable size into the inner cavity. A high negative electrostatic potential on the portals 3 is responsible for the formation of stable inclusion compounds of CB[n] with positively charged guests, for example, with alkylammonium cations. 2,3 The cavity sizes in cucurbit[n]urils with n > 6 are sufficient for the inclu sion of metal complexes with small organic ligands. The spectroscopic (NMR), calorimetric, and electrochemical studies showed that highly stable host-guest compounds are formed. 5-9 However, only a few inclusion com pounds of CB[n] with metal complexes were structurally characterized. 6,10-12 Complexes included into the bar rel shaped cavity of CB[n] can be fully embedded in the cavitand, as opposed to most of inclusion compounds of such receptors as calixarenes and cyclodextrins where com plexes are only partially encapsulated in the bowl shaped cavities. 13 In recent years, this class of compounds has attracted considerable interest because of the possibility of the inclusion of biologically active metal complexes into cavitands. This opens wide opportunities for the design of new generation prolonged action pharmaceuticals in which the host molecules prevents the guest molecules from rapid decomposition, decrease their toxicity, and have the transport function of the active component in the organism. 14 Recent studies 14-16 have shown that the in clusion of platinum polyamine complexes having antitu mor activity into cucurbit[n]urils leads to a substantial decrease in the toxicity of these complexes. Antitumor drugs containing inclusion compounds of CB[7] and CB [8] with platinum, palladium, and gold complexes were cov ered by patents. 17-20Previously, 21-25 we have shown that CB[8] forms inclusion compoun...

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