RESUMO
The synthesis and solid-state structure of mononuclear copper(II) complexes [Cu(SAIB)(H(2)O)(2)] (1), [Cu(SBAIB)(H(2)O)(2)]·H(2)O (2) and [Cu(SGABA)(H(2)O)(2)] (3) are described. Schiff base ligands H(2)SAIB, H(2)SBAIB and H(2)SGABA chelate the copper(II) ion in an O,N,O tridentate fashion. The square-pyramidal geometry of the final complexes is completed by two water ligands. The formation of an unusual seven-membered ring in the set of copper(II) N-salicylidene-aminoacidates is reported. Compounds 1-3 were evaluated by the antiradical activity assay.
Assuntos
Cobre/química , Compostos Heterocíclicos de 4 ou mais Anéis/química , Compostos Organometálicos/química , Compostos Organometálicos/síntese química , Bases de Schiff/química , Cristalografia por Raios X , Modelos Moleculares , Estrutura Molecular , EstereoisomerismoRESUMO
The surface structure of an individual metal-organic framework (MOF) microcrystal grown on a functionalized surface has been successfully investigated for the first time in air and vacuum using high-resolution atomic force microscopy. Moreover, this detailed surface analysis has been utilized to optimize the MOF formation procedure to obtain a defect-free surface structure. Comparison of obtained data with recent microscopic studies performed on the same MOF crystal but grown by a conventional procedure clearly shows a much higher quality of crystals produced by surface oriented growth. Importantly, this method of preparing crystals suitable for microscopic analysis is also much faster (3 days compared to 2 years) and, in contrast to the conventional method, produces material suitable for in situ study. These results thus demonstrate for the first time the possibility of nanoscale investigation/modification of MOF surface structure.
Assuntos
Cobre/química , Compostos Organometálicos/química , Dióxido de Silício/química , Silício/química , Ácidos Tricarboxílicos/química , Cristalização , Microscopia de Força Atômica , Microscopia Eletrônica de Transmissão , Nanopartículas/química , Propriedades de SuperfícieRESUMO
4-Heteroarylidene-2-phenyl-1,3-oxazol-5(4H)-ones were prepared by reactions of hippuric acid with substituted furan-2-carboxaldehydes or furo[b]pyrrole type aldehydes. The reactivity of various furan-2-carboxaldehyde derivatives in this reaction is discussed. The effect of microwave irradiation on some condensation reactions was compared with "classical" conditions. The results show that microwave irradiation shortens the reaction times while affording comparable yields. Elementary analysis, UV, IR and 1D NMR proved the structure of new synthesised compounds. 2D NMR spectroscopic measurements confirmed that the configuration at the carbon-carbon double bond corresponds to the pure E isomers of the products.
Assuntos
Aldeídos/química , Furanos/síntese química , Hipuratos/química , Pirróis/síntese química , Furanos/química , Micro-Ondas , Conformação Molecular , Estrutura Molecular , Pirróis/químicaRESUMO
A series of new push-pull compounds were synthesised by reaction of 5-aryl- furan-2-carboxaldehydes and furo[b]pyrrole type aldehydes with benzothiazolium salts. These new condensation products represent highly conjugated systems that have potential biological activity. The reaction of furo[b]pyrrole type aldehydes with benzothiazolium salts give potential precursors of cyanine dyes.
