“…, catalysts), materials science, and nano-chemistry to biochemistry. 15–19 The sensitivity to the nature of ligands in the coordination sphere, the oxidation state of metals, various coordination numbers and the possible geometries sometimes make the NMR peak assignment difficult. Over the last few decades DFT NMR calculations have been employed complementarily to the experimental data for the interpretation of complex NMR spectra.…”
Because of their chemical heterogeneity, stereochemical complexity and the presence of heavy atoms involving orbitals with high quantum number L, organopolymetallic complexes require considerable attention within their NMR spectra interpretation....
“…, catalysts), materials science, and nano-chemistry to biochemistry. 15–19 The sensitivity to the nature of ligands in the coordination sphere, the oxidation state of metals, various coordination numbers and the possible geometries sometimes make the NMR peak assignment difficult. Over the last few decades DFT NMR calculations have been employed complementarily to the experimental data for the interpretation of complex NMR spectra.…”
Because of their chemical heterogeneity, stereochemical complexity and the presence of heavy atoms involving orbitals with high quantum number L, organopolymetallic complexes require considerable attention within their NMR spectra interpretation....
“…(3) Cationic systems, with diamine 35 – 38 , bisphosphine 39 , 40 , carbene 41 – 43 or pincer ligands 44 – 46 ; in particular, Gagné discovered a series of elegant cationic Pt(II) complexes, such as (PPP)Pt 2+ and (PP)PPt 2+ , which efficiently inhibit β -H elimination as a competing decomposition pathway 31 , 40 , 46 . Among the three activation modes, coordination to the cationic Pt derivatives renders the multiple bonds more electrophilic and thus susceptible to nucleophilic attack 47 , 48 . Fig.…”
Hydrofunctionalization, the direct addition of an X–H (e.g., X=O, N) bond across an alkene, is a desirable strategy to make heterocycles that are important structural components of naturally occurring molecules. Described here is the design and discovery of “donor–acceptor”-type platinum catalysts that are highly effective in both hydroalkoxylation and hydroamination of unactivated alkenes over a broad range of substrates under mild conditions. A number of alkene substitution patterns are accommodated, including tri-substituted, 1,1-disubstituted, (E)-disubstituted, (Z)-disubstituted and even mono-substituted double bonds. Detailed mechanistic investigations suggest a plausible pathway that includes an unexpected dissociation/re-association of the electron-deficient ligand to form an alkene-bound “donor–acceptor”-type intermediate. These mechanistic studies help understand the origins of the high reactivity exhibited by the catalytic system, and provide a foundation for the rational design of chiral catalysts towards asymmetric hydrofunctionalization reactions.
“…In this regard, the Zeise’s anion, [PtCl 3 (η 2 -C 2 H 4 )] − , showing an extreme lability of the trans to olefin chlorido ligand and a peculiar reactivity of the coordinated ethene, resulted to be a suitable precursor for the synthesis of new antitumor organometallic complexes [ 19 ]. In fact, it allows the formation of platinum(II) organometallic complexes by the promotion of coordination in the platinum(II) sphere of specific carrier ligands and the exploitation of the intrinsic π-acid character of platinum-coordinated η 2 -ethene [ 36 , 37 , 38 , 39 ]. We already explored the synthetic possibilities offered by the peculiar reactivity of the Zeise’s anion in strongly basic oxydrilated solvents, demonstrating that in these conditions, anionic species of the type trans -[PtCl 2 (η 2 -C 2 H 4 )(OR)] − (R = H, alkyl) are easily formed.…”
Starting from the [PtCl(η1-C2H4OMe)(phen)] (phen = 1,10-phenanthroline, 1) platinum(II) precursor, we synthesized and characterized by multinuclear NMR new [Pt(η1-C2H4OMe)(L)(phen)]+ (L = NH3, 2; DMSO, 3) complexes. These organometallic species, potentially able to interact with cell membrane organic cation transporters (OCT), violating some of the classical rules for antitumor activity of cisplatin analogues, were evaluated for their cytotoxicity. Interestingly, despite both complexes 2 and 3 resulting in greater cell uptake than cisplatin in selected tumor cell lines, only 3 showed comparable or higher antitumor activity. General low cytotoxicity of complex 2 in the tested cell lines (SH-SY5Y, SK-OV-3, Hep-G2, Caco-2, HeLa, MCF-7, MG-63, ZL-65) appeared to depend on its stability towards solvolysis in neutral water, as assessed by NMR monitoring. Differently, the [Pt(η1-C2H4OMe)(DMSO)(phen)]+ (3) complex was easily hydrolyzed in neutral water, resulting in a comparable or higher cytotoxicity in cancer cells with respect to cisplatin. Further, both IC50 values and the uptake profiles of the active complex appeared quite different in the used cell lines, suggesting the occurrence of diversified biological effects. Nevertheless, further studies on the metabolism of complex 3 should be performed before planning its possible use in tissue- and tumor-specific drug design.
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