N-(2-Nitro­oxyeth­yl)picolinamide

In the title mol­ecule, C8H9N3O4, the amide group is involved in the formation of an intra­molecular N—H⋯N hydrogen bond. In the crystal, mol­ecules related by translation along the a axis are linked into chains via weak inter­molecular C—H⋯O inter­actions

A dimensão institucional no processo de socialização de professores de química em início de carreira

Este trabalho analisa as vivências de três professoras de química em início de carreira e tem por objetivo compreender como ocorre o processo de socialização delas com a cultura escolar e, também, identificar quais os conflitos e influências que emergem da relação dessas professoras com a dimensão institucional. Para tanto, utilizamos a abordagem qualitativa de estudo de caso do tipo etnográfico. Observamos, como reconhece a literatura, que o início da docência é uma fase difícil na qual o professor se sente sozinho e pressionado para se socializar com a cultura escolar. Os resultados evidenciaram que a instituição, representada pelos dirigentes e os pares, não ofereceu o apoio esperado pelas professoras em início de carreia e, ainda, não colaborou para a integração delas ao corpo profissional da escola. As influências desse processo podem afetar tanto a prática e constituição do professor iniciante quanto à sua permanência na carreira docente

Bis(tetra­phenyl­phospho­nium) bis­[N-(trifluoro­methyl­sulfon­yl)dithio­carbimato(2−)-κ2 S,S′]zincate(II)

The title salt, (C24H20P)2[Zn(C2F3NO2S3)2], consists of a complex dianion and two tetra­phenyl­phospho­nium cations. The ZnII ion displays a distorted tetra­hedral coordination environment with four S atoms from two S,S′-chelated N-(trifluoro­methyl­sulfonyl­)dithio­carbimate anions. In the crystal, besides the ionic inter­action of the oppositely charged ions, inter­molecular C—H⋯O inter­actions between cations and anions are observed. One of the cations inter­acts with an inversion-related equivalent by π–π stacking between phenyl rings, with a centroid–centroid distance of 3.932 (4) Å

6-Methoxyisobenzofuran-1(3H)-one

In the title compound, C9H8O3, the molecular skeleton is almost planar [r.m.s. deviation = 0.016 (2) Å]. Weak intermolecular C—H...O and C—H...π interactions consolidate the crystal packing, with the molecules stacking in the [101] direction

fac-[1,2-Bis(pyridin-4-yl)ethane-κN]tricarbonyl(1,10-phenanthroline-κ2N,N′)rhenium(I) hexafluoridophosphate acetonitrile monosolvate

The asymmetric unit of the title compound, [Re(C12H8N2)(C12H12N2)(CO)3]PF6.·CH3CN, contains one cation, one hexafluoridophosphate anion and one acetonitrile solvent molecule. The ReI ion is coordinated by two N atoms from the 1,10-phenanthroline ligand and one N atom from the 1,2-bis(pyridin-4-yl)ethane ligand [mean Re—N = 2.191 (15) Å] and by three carbonyl ligands [mean Re—C = 1.926 (3) Å] in a distorted octahedral geometry. The electrostatic forces and weak C—H...F(O) hydrogen bonds pack cations and anions into the crystal with voids of 82 Å3, which are filled by solvent molecules. The crystal packing exhibits short intermolecular O...O distance of 2.795 (5) Å between two cations related by inversion

Centrosymmetric resonance-assisted intermolecular hydrogen bonding chains in the enol form of ␤-diketone: Crystal structure and theoretical study

Isobenzofuran-1(3H)-ones (phtalides) are heterocycles that present a benzene ring fused to a γ-lactone functionality. This structural motif is found in several natural and synthetic compounds that present relevant biological activities. In the present investigation, the 3-(2-hydroxy-4,4-dimethyl-6-oxocyclohexen-1-yl)isobenzofuran-1(3H)-one was characterized by single-crystal X-ray analysis. In the crystal structure, there are two molecules per asymmetric unit. One of them exhibits resonance assisted hydrogen bonds (RAHBs). Semi-empirical and DFT calculations were performed to obtain electronic structure and π-delocalization parameters, in order to better understand the energy stabilization of RAHBs in the crystal packing of the studied molecule. The structural parameters showed good agreement between theoretical and experimental data. The theoretical investigation revealed that the RAHBs stabilization energy is directly related to the electronic delocalization of the enol form fragment. In addition, RAHBs significantly affected the HOMO and charge distribution around the conjugated system

Syntheses, characterization and antifungal activity of heteroleptic nickel(II) complexes with N-alkylsulfonyldithiocarbimates and phosphines

Four nickel(II) complexes of general formula [Ni(RSO2NCS2) (PPh3)2] where R = CH3 (2a), CH3CH2 (2b), CH3(CH2)3 (2c) and CH3(CH2)7 (2d) and PPh3 = triphenylphosphine; and two nickel(II) complexes of general formula [Ni(RSO2NCS2)dppe] where R = CH3(CH2)3 (3c) and CH3(CH2)7 (3d) and dppe = 1,2-bis(diphenylphosphine)ethane) were prepared. These new complexes were obtained by the reaction of nickel(II) chloride hexahydrate with potassium N-alkylsulfonyldithiocarbimates and the appropriate phosphine using ethanol/water as solvent. The IR, UV–Vis and ^1 H, ^13 C and ^31 P NMR spectra, elemental analysis of Ni and the HR-ESI-MS were consistent with the formation of square planar nickel(II) complexes with mixed ligands. The structures of the compounds 2b and 2c were determined by single crystal X-ray diffraction. The compounds are isostructural and crystallize in the space group P of the triclinic system. The activities of the complexes were investigated in vitro against Botrytis cinerea, Colletotrichum acutatum and Alternaria solani, fungi species that affect various commercially important plants. All the complexes were active