Search results for "Cyanide"

CCDC 1427488: Experimental Crystal Structure Determination

2015

Related Article: Eugenio Coronado, M. Carmen Giménez-López, Tomasz Korzeniak, Georgiy Levchenko, Francisco M. Romero, Alfredo Segura, Valentín García-Baonza, Julio C. Cezar, Frank M. F. de Groot, Alla Milner, Moshe Paz-Pasternak|2008|J.Am.Chem.Soc.|130|15519|doi:10.1021/ja8047046

Mechanism of aminocarbene formation by nucleophilic attack on isocyanide ligands in platinum(II)2-pyrazyl and 4-pyridyl complexes

1997

Abstract The reactions of 2-pyrazyl and 4-pyridyl isocyanide complexes [Pt(CNC 6 H 11 )(C 4 H 3 N 2 - C 2 )(dppe)ClO 4 and [Pt(CNC 6 H 11 )(C 5 H 4 N- C 4 ) (dppe)]ClO 4 ( 1 ) with amines involving the formation of aminocarbene derivatives have been studied kinetically in 1,2-dichloroethane by UV—VIS techniques. The kinetics obey the simple second-order rate law rate = k 2 [ 1 ][amine]. Low activation enthalpies and highly negative activation entropies for the k 2 term are observed. A mechanism is proposed involving direct nucleophilic attack of the amine on the isocyanide carbon with concomitant proton transfer from the amine to the isocyanide nitrogen assisted by the heterocyclic nitrogen…

Pressure-tuning of magnetism and linkage isomerism in iron(II) hexacyanochromate.

2005

A pressure-induced linkage isomerization of the cyanide anion has been observed in single crystals of a chromium(III)-iron(II) Prussian blue analogue of formula K0.4Fe4[Cr(CN)6]2.8 square1.2.16H2O (1). Upon application of pressure in the 0-1200 MPa range, the cyanide ligand rotates and becomes C-bonded to the iron(II) cations, leading to a stabilization of their diamagnetic low-spin states. The result is a decrease of magnetization and magnetic ordering temperatures from TC = 19 K at ambient pressure to 13 K at 1200 MPa. The initial magnetic properties can be restored on pressure release. The reversible movement of cyanide in the solid state can be exploited as a switch of the magnetic inte…

Metal-to-metal electron transfer and magnetic interactions in a mixed-valence Prussian Blue analogue

2006

Abstract In search of a new Prussian Blue analogue exhibiting fascinating magnetic properties, potassium manganese hexacyanoferrate, K 0.2 Mn 0 . 66 II Mn 1.44 III [ Fe 0.2 II Fe 0.8 III ( CN ) 6 ] O 0.66 ( CH 3 COO ) 1.32 ] , 7.6H2O, has been synthesized. This compound undergoes a paramagnetic to ferrimagnetic transition at 10 K. Temperature and magnetic field-dependent magnetization studies of this compound have revealed different spin alignments below and above 3 K. The nature of possible magnetic interactions between the nearest neighbor magnetic centers has been discussed in order to explore the origin of the observed magnetic interactions. Mossbauer spectroscopic study at different te…

Self-assembly mechanism of nanoparticles of Ni-based Prussian Blue analogues at the air/liquid interface: a synchrotron X-ray reflectivity study.

2015

Prussian Blue analogue (PBA) nanoparticles can be self-assembled at air/liquid interfaces to build novel materials with interesting magnetic features. Herein, we study the influence of the size of PBA Cs0.4 Ni[Cr(CN)6 ]0.9 and K0.25 Ni[Fe(CN)6 ]0.75 nanoparticles on the self-assembly behavior by synchrotron X-ray reflectivity. Both nanoparticles show similar Z-potential values. The phospholipid dipalmitoylphosphatidylcholine and the amino surfactant dimethyldioctadecylammonium have been used as Langmuir monolayers to anchor the PBA nanoparticles and study the interplay of forces directing the self-assembly of the nanoparticles at the surfactant/liquid interface. Whereas Cs0.4 Ni[Cr(CN)6 ]0.…

A Mixed-Valence Mixed-Spin Prussian-Blue-Like Heptanuclear Complex

2000

A novel octacyanido dicobalt(iii) building block for the construction of heterometallic compounds

2019

The first bimetallic octacyanido complex of CoIII, (PPh4)2[Co2(μ-2,5-dpp)(CN)8] (1), was synthesized and used as a metalloligand with [Mn(MAC)(H2O)2]Cl2·4H2O to give a new {CoIIIMnII} heterometallic chain of formula [MnII(MAC)(μ-NC)2Co2III(μ-2,5-dpp)(CN)6]n·7nH2O (2) (PPh4+ = tetraphenylphosphonium cation; 2,5-dpp = 2,5-bis(2-pyridyl)pyrazine and MAC = 2,13-dimethyl-3,6,9,12,18-pentaazabicyclo-[12.3.1]octadeca-1(18),2,12,14,16-pentaene). Both compounds were characterized by single-crystal X-ray diffraction. Compound 1 contains a diamagnetic 2,5-dpp-bridged dicobalt(III) unit with four peripheral cyanide ligands at each cobalt center achieving a six-coordinate surrounding, the electroneutral…

Reversible complexation of ethylene by a silylene under ambient conditions.

2014

Treatment of toluene solutions of the silylenes Si(SArMe6)2 (ArMe6 = C6H3-2,6(C6H2-2,4,6-Me3)2, 1) or Si(SArPri4)2 (ArPri4 = C6H3-2,6(C6H3-2,6-Pri2)2, 2) with excess ethylene gas affords the siliranes (ArMe6S)2tiebar above startSiCH2tiebar above endCH2 (3) or (ArPri4S)2tiebar above startSiCH2tiebar above endCH2 (4). Silirane 4 evolves ethylene spontaneously at room temperature in toluene solution. A Van’t Hoff analysis by variable-temperature 1H NMR spectroscopy showed that ΔGassn = −24.9(2.5) kJ mol–1 for 4. A computational study of the reaction mechanism using a model silylene Si(SPh)2 (Ph = C6H5) was in harmony with the Van’t Hoff analysis, yielding ΔGassn = −24 kJ mol–1 and an activatio…

Selective and Sensitive Chromogenic Detection of Cyanide and HCN in Solution and in Gas Phase

2013

Two triphenylmethane based chemodosimeters for selective and chromogenic sensing of cyanide anions in aqueous environments and of hydrogen cyanide in gas phase were prepared and studied.

NEW 5-DIMETHYL-3-HETEROARYL-1H-4-ONN-AZOXYCYANIDES: SYNTHESIS AND ANTIMICOTICAL ACTIVITY.

2014

In the field of infectious diseases, in the last years an increasingly high importance is ascribed to mycosis as causes of illness and mortality in particularly susceptible patients: leukemia, organ transplant, AIDS and immunosuppressed patients, creating clinical and epidemiological problems. Although several drugs are available, antifungal spectrum is still limited especially for invasive infections, which often have fatal results. We previously reported the antifungal activity of a series of products, in which the 1,5-dimethyl-4-(cyano-NNO-azoxy)pyrazol-3-yl and 1,3-dimethyl-4-(cyano-NNO-azoxy)pyrazol-5-yl moieties were linked to pyridine, pyrazole, isoxazole, thiophene and the furan rin…