Search results for "Complexes."

Disrupting neural activity related to awake-state sharp wave-ripple complexes prevents hippocampal learning

2012

Oscillations in hippocampal local-field potentials (LFPs) reflect the crucial involvement of the hippocampus in memory trace formation: theta (4–8 Hz) oscillations and ripples (~200 Hz) occurring during sharp waves are thought to mediate encoding and consolidation, respectively. During sharp wave-ripple complexes (SPW-Rs), hippocampal cell firing closely follows the pattern that took place during the initial experience, most likely reflecting replay of that event. Disrupting hippocampal ripples using electrical stimulation either during training in awake animals or during sleep after training retards spatial learning. Here, adult rabbits were trained in trace eyeblink conditioning, a hippoc…

Structure ofD-ribonic acid-dimethyltin(IV) in coordinating solvents: an experimental and DFT119Sn NMR study

2006

We have investigated a newly synthesized complex of D-ribonic acid with dimethyltin(IV). The structure of the complex in solution has been characterized by means of 1 H, 13 C, and 119 Sn NMR and by DFT calculations. The comparison of experimental and computational results allowed the determination of the stable conformation in solution as well as the detection of a dimerization process. Moreover, evidence is given of active coordination of the metal by the solvent.

Synthesis, structural characterization and antitumor activity of di- and tri-organotin(IV) complexes of D-galacturonic acid

2015

A Cation-Captured Palladium(0) Anion: Synthesis, Structure, and Bonding of [PdBr(PPh3)2]− Ligated by an N-Heterocyclic Phosphenium Cation

2009

Unsaturated N-heterocyclic phosphenium cations (uNHP) stabilize the [Pd0(PR3)2X]− anion proposed over the past decade to be the crucial but elusive intermediate in palladium-catalyzed cross-coupling reactions (X = halide). Insertion of metal into the P−Br bond of the precursor mesityl-substituted bromophosphine gives the structurally characterized Pd(0)-phosphenium complex (uNHPMes)Pd(PPh3)2Br, which features a long Pd−Br bond (2.7240(9) Å) and the shortest known Pd−P bond (2.1166(17) Å). The reaction is proposed to proceed by an associative pathway involving a Pd-bromophosphine complex that undergoes P-to-Pd bromide transfer. peerReviewed

Structural and electronic elucidation of a N-heterocyclic silylene vanadocene adduct

2017

The solid and solution state structure of the vanadium(II) N‐ heterocyclic silylene (NHSi) complex, [(SiIPr)V(Cp)2] (1) is reported ( SiIPr: 1,3‐bis(2,6‐diisopropylphenyl)‐1,3‐diaza‐2‐silacyclopent‐4‐ en‐2‐ylidene). The electronic structure of 1 is probed using combination of magnetic measurements, EPR spectroscopy and computational studies. The V–Si bond strength and complex forming mechanism between vanadocene and NHSi ligand is elucidated using computational methods.   peerReviewed

Host-guest interactions between DMpillar[5]arene and fluorescent imidazolium salts

Non-conventional synthesis and photophysical studies of platinum(ii) complexes with methylene bridged 2,2′-dipyridylamine derivatives

2019

Methylene bridged 2,2′-dipyridylamine (dpa) derivatives and their metal complexes possess outstanding properties due to their inherent structural flexibility. Synthesis of such complexes typically involves derivatization of dpa followed by coordination on metals, and may not always be very efficient. In this work, an alternative synthetic approach, involving the derivatization step after – rather than prior to – coordination of dpa on metal center, is proposed and applied to synthesis of a number of platinum(II) complexes with substituted benzyldi(2-pyridyl)amines. Comparison with the more conventional synthetic route reveals greater efficiency and versatility of the proposed approach. The …

Homoleptic Pnictogen-Chalcogen Coordination Complexes

2012

The synthesis and structural characterization of dicationic selenium and tellurium analogues of the carbodiphosphorane and triphosphenium families of compounds are reported. These complexes, [Ch(dppe)][OTf]2 [Ch = Se, Te; dppe = 1,2-bis(diphenylphosphino)ethane; OTf = trifluoromethanesulfonate], are formed using [Ch]2+ reagents via a ligand-exchange protocol and represent extremely rare examples of homoleptic pnictogen → chalcogen coordination complexes. The corresponding arsenic compounds were also prepared, [Ch(dpAse)][OTf]2 [Ch = Se, Te; dpAse = 1,2-bis(diphenylarsino)ethane], exhibiting the first instance of an arsenic → chalcogen dative bond. The electronic structures of these unique c…

Complex species formation of Cu and Cd metal ions with polyacrylate, polymethacrylate and alginate ligands. Potentiometric investigation by ISE-H+ an…

2008

Diversity of Isomerization Patterns and Protolytic Forms in Aminocarbene PdII and PtII Complexes Formed upon Addition of N,N′-Diphenylguanidine to Me…

2017

Reaction of the palladium(II) and platinum(II) isocyanide complexes cis-[MCl2(CNR)2] [M = Pd, R = C6H3(2,6-Me2) (Xyl), 2-Cl-6-MeC6H3, cyclohexyl (Cy), t-Bu, C(Me)2CH2(Me)3 (1,1,3,3-tetramethylbuth-1-yl abbreviated as tmbu); M = Pt, R = Xyl, 2-Cl-6-MeC6H3, Cy, t-Bu, and tmbu] with N,N′-diphenylguanidine (DPG) leads to DPG-derived metal-bound deprotonated acyclic diaminocarbene (ADC) species. This reaction occurs via a two-step process, involving the initial coupling of the guanidine with one of the isocyanides and leading to deprotonated monocarbene monochelated species, while the next addition grants the deprotonated bis-carbene bis-chelated metal compounds. DPG behaves as nucleophile, depr…