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Crystal structure of the gold(I) complex [Au(tfp)Cl] with tfp =(C4H3O)(3)P
No full textThe Au(I) complex [Au(tfp)Cl] with tfp = (C4H3O)3P has been prepared and characterised.
It crystallises in the monoclinic P21/n space group with z = 4, a = 9.837(3),
b = 12.684(4), c = 11.103(5)A° , β = 91.58(2)◦ and V = 1384.8(2)°A3. The structure of the
complex consists of molecules connected in head-to-tail dimers by a metal-halogen contact
as generally found in analogus complexes of lighter coinage metals. The typical feature of
halogen gold compounds, the Au Au interaction, seems prevented by the bulk of the tfp
ligand
Reactions of (tertiary phosphine)gold(I) substituted imidazoles or pyrazolones with acidic reagents: protonation, azole displacement, and adduct formation. Crystal structure determination of the adduct 1-methyl-2-(cyclohexylphosphinegoldthiolato)imidazole.2benzimidazole
No full textElectrospray mass spectrometry characterization of ionic silver(I) and gold(I) complexes of the ligand L = 1-benzyl-2-imidazolyl-diphenylphosphine. Counterion influence in the ionization processes and crystal structure determination of [Ag2L3][CF3SO3]2.
No full textOne of the most discussed and studied aspects of the silver(I) coordination complexes chemistry is the influence of the counterions in the solid state structures and in the ligand exchange reactions occurring in solution; this kind of chemistry is pretty rare in the gold(I) coordination derivatives. Some silver(I) and gold(I) complexes of the type L2M2X2 (where L is 1-benzyl-2-imidazolyl diphenylphosphine I, M = Ag, X = BF4 II; X=NO3 III, X=CF3SO3 IV, X = BAr4 V), L3M2X2 (M = Ag, X =NO3 VI, X=BF4 VII, X = BAr4 VIII, X =CF3SO3 IX), LAuCl (X), L2Au2X2 (X = BF4, XI) and L2AuBF4 (XII) have been synthesized. In the paper is reported the unprecedented structure of IX. From the analysis of the structures, it can be argued that in the silver(I) complexes the counterions deeply affect the structure by strongly interacting with the metal centres. In addition it is also reported the study of these complexes by the ESI mass spectrometry with the target of both studying the counterion effect in the ionization process, and to characterize the above described complexes by this new soft mass spectrometry technique
A single-strand helical motif induced by self-assembly of [Ag(TFP)]+ moieties with nitrate anions - 31P NMR spectroscopic and X-ray crystal structure characterization of the complexes involved in equilibrium reactions of silver salts and TFP ligand
No full textDiastereoisomeric Forms of alpha,alpha’-diphenyl-substituted Adiponitriles
No full textThe preparation of some adiponitriles with two equivalent asymmetric carbon atoms in the alpha-alpha' positions is described. The two diastereoisomeric forms isolated for each of them are assigned meso and dl configurations on the basis of a detailed analysis of the NMR signals of the -CH2-CH2- groups, which constitute an AA'BB' spin-spin coupling system. The differences in physical properties of the meso and dl compounds are examined, and some partial and total hydrolysis reactions are described
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Chemistry and Optoelectronic Properties of Stacked Supramolecular Entities of Trinuclear Gold(I) Complexes Sandwiching Small Organic Acids
No full textVariations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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