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1.
Chemistry ; 26(31): 6993-6998, 2020 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-32182384

RESUMEN

The photophysical properties of a series of T-shaped coinage d10 metal complexes, supported by a bis(mesoionic carbene)carbazolide (CNC) pincer ligand, are explored. The series includes a rare new example of a tridentate T-shaped AgI complex. Post-complexation modification of the AuI complex provides access to a linear cationic AuI complex following ligand alkylation, or the first example of a cationic square planar AuIII -F complex from electrophilic attack on the metal centre. Emissions ranging from blue (CuI ) to orange (AgI ) are obtained, with variable contributions of thermally-dependent fluorescence and phosphorescence to the observed photoluminescence. Green emissions are observed for all three gold complexes (neutral T-shaped AuI , cationic linear AuI and square planar cationic AuIII ). The higher quantum yield and longer decay lifetime of the linear gold(I) complex are indicative of increased phosphorescence contribution.

3.
Angew Chem Int Ed Engl ; 58(10): 2912-2913, 2019 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-30701633

RESUMEN

"The entire field of science needs to enhance its performance with regard to equality, diversity, and inclusion …" Read more in the Editorial by S. A. Matlin, V. W. W. Yam et al.

4.
Angew Chem Int Ed Engl ; 57(45): 14690-14698, 2018 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-30079534

RESUMEN

There has been mounting concern over the absence of gender equality in the sciences in recent years. This has been accompanied by a broadening of the perspective, in order to address issues of equality, diversity and inclusion, relating to a wide range of circumstances in which individuals suffer discrimination. While some progress has been made in some countries, nationally or at the level of institutions, much more needs to be done. The chemical sciences can play a leading role in addressing biases, through 1) becoming a model of good systemic practice in policies, processes, and actions; 2) developing practical skills through training in cultural competence; and 3) promoting a stronger evidence base to uncover both the extent of problems and the degree to which approaches to improve equality, diversity, and inclusion are working.


Asunto(s)
Química , Competencia Cultural , Investigación , Discriminación Social , Química/educación , Química/legislación & jurisprudencia , Química/organización & administración , Competencia Cultural/legislación & jurisprudencia , Competencia Cultural/organización & administración , Diversidad Cultural , Femenino , Humanos , Masculino , Investigación/educación , Investigación/legislación & jurisprudencia , Investigación/organización & administración , Sexismo/legislación & jurisprudencia , Sexismo/prevención & control , Discriminación Social/legislación & jurisprudencia , Discriminación Social/prevención & control
5.
J Am Chem Soc ; 138(41): 13732-13739, 2016 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-27670800

RESUMEN

New tetranuclear supramolecular precursors [(R-C≡C-C≡C)Ag]4 (R = iPr, tBu, and chx) are employed to construct a series of heterometallic silver(I)-copper(I) alkyl-1,3-diynyl cluster complexes (1-9) that bear a common CuAg3 core (normally trigonal-planar, but can be distorted to pyramidal) consolidated by cupro-argentophilic interaction under 3.12 Å, as found in 1 and 2. The photophysical properties of the multinuclear supramolecular precursors and selected complexes have been investigated. The present results strongly suggest that the assembly of medium-nuclearity clusters 3 to 9 is initiated by accretion of additional Ag(I) ions by the ubiquitous CuAg3 template through argentophilic (<3.4 Å) interaction, with cooperative cuprophilic enhancement (<2.76 Å) in the case of compound 9. To our knowledge, the present study provides the first report of conversion of a Group 11 homonuclear cluster into a heteronuclear one of higher nuclearity via inner-core expansion.

6.
Chemistry ; 22(24): 8032-7, 2016 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-27142245

RESUMEN

A novel class of chiral luminescent square-planar platinum complexes with a π-bonded chiral thioquinonoid ligand is described. Remarkably the presence of this chiral organometallic ligand controls the aggregation of this square planar luminophor and imposes a homo- or hetero-chiral arrangement at the supramolecular level, displaying non-covalent Pt-Pt and π-π interactions. Interestingly these complexes are highly luminescent in the crystalline state and their photophysical properties can be traced to their aggregation in the solid state. A TD-DFT calculation is obtained to rationalize this unique behavior.

10.
J Am Chem Soc ; 132(46): 16383-92, 2010 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-21033663

RESUMEN

This paper is concerned with the synthesis and reactions of enantiopure 1,8,9,16-tetraethynyltetraphenylene (3). We obtained 3 in 34% yield through four steps starting from 1,8,9,16-tetrahydroxytetraphenylene (2a) via a functional group interconversion strategy. On the basis of this chiral "helical" building block, three rigid helical macrocycles 14, 15, and 22 were designed. Complexes 14 and 15 were constructed via coordination-driven self-assembly with platinum(II) complexes 8 and 9b, while 22 cannot be obtained successfully. Then macrocycle 28 was designed on the structural basis of 22 to which octyl chains were introduced, in the hope of improving the solubility of the complex. Macrocycle 28 was finally formed and was characterized by NMR spectroscopy, elemental analysis, and electrospray mass spectrometry. For the enantiopure 15 and 28, circular dichroism (CD) spectra also exhibited chiral properties. Complexes 27 and 28 both exhibited an intense emission band at 621 nm in acetonitrile at 298 K upon excitation at λ > 420 nm.

13.
Nat Chem ; 2(9): 790, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20729904

RESUMEN

As a rare and precious metal that is also resistant to wear and tarnish, platinum is known to be particularly well-suited to jewellery. Vivian Yam reflects on how, beyond its prestigious image, platinum has also found its way into a variety of fields ranging from the petrochemical to the pharmaceutical industry.


Asunto(s)
Platino (Metal)/química , Catálisis , Compuestos Organoplatinos/química , Compuestos Organoplatinos/farmacología
14.
Angew Chem Int Ed Engl ; 39(23): 4240-4242, 2000 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-29711914
16.
Org Lett ; 11(19): 4302-5, 2009 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-19722507

RESUMEN

Nucleic acid was found to induce the aggregation of the positively charged pyrene probe (compound 1); as a result, strong pyrene excimer emission was observed. The intensity of the excimer emission was dependent on the concentration of the pyrene probe and the oligonucleotide length, sequence, and concentration. These results suggest a new strategy for label-free nucleic acid-based biosensing applications.


Asunto(s)
Colorantes Fluorescentes/química , Ácidos Nucleicos/química , Pirenos/química , Colorantes Fluorescentes/síntesis química , Estructura Molecular , Pirenos/síntesis química
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