Extracurricular laboratory:new discovery of 448-61-3

Note that a catalyst decreases the activation energy for both the forward and the reverse reactions and hence accelerates both the forward and the reverse reactions.category: catalyst-ligand, you can also check out more blogs about448-61-3

Chemistry is traditionally divided into organic and inorganic chemistry. category: catalyst-ligand. The former is the study of compounds containing at least one carbon-hydrogen bonds.In a patent，Which mentioned a new discovery about 448-61-3

Noncovalent interactions of anions with electron-deficient aromatic rings that have been studied so far involve non-heteroaromatic or nitrogen-based heteroaromatic systems. Here we report the first case of an organic oxygenated aromatic system, in particular the tri-aryl-pyrylium tetrafluoroborate system, for which noncovalent anion-pi interactions of the pyrylium cation with the tetrafluoroborate anion have been experimentally detected and demonstrated by means of 19F NMR spectroscopy in solution. A series of pyrylium tetrafluoroborate salts were synthesized in the presence of BF 3·Et2O, by direct reaction of 4-substituted benzaldehydes with 4-substituted acetophenones or via the previously obtained chalcone of the less reactive ketone. Correlations of 19F NMR chemical shifts of tetrafluoroborate anion for most of the synthesized tri-arylpyrylium tetrafluoroborate complexes with both the pyrylium cation molecular weight and the standard substituent Hammett constants, demonstrate anion-pi+ interaction to act between the polyatomic anion BF 4- and the pyrylium aromatic system. DFT calculations reveal that an additional (C-H)+-anion hydrogen bond involving the H(5) of pyrylium ring exists for these fluorescent dyes that show a tunable cup-to-cap shape cavity. The strong fluorescence emission observed for some representative pyrylium tetrafluoroborates described herein, makes them a promising class of tunable emission wavelength dyes for laser technology applications. the Partner Organisations 2014.

Note that a catalyst decreases the activation energy for both the forward and the reverse reactions and hence accelerates both the forward and the reverse reactions.category: catalyst-ligand, you can also check out more blogs about448-61-3

Reference：
Metal catalyst and ligand design,
Ligand Template Strategies for Catalyst Encapsulation – NCBI