89635-79-0Relevant articles and documents
Pyrene-containing dyes: Reversible click/declick reaction, optical and aggregation behaviors
Peng, Mengde,Wang, Ying,Zhang, Xin
, (2020)
Pyrene-based dyes were synthesized by a clean, efficient Diels-Alder [4 + 2] click reaction where no catalyst adding or side reactions occurring. The optical behaviors, optoelectronic properties and supramolecular donor/acceptor dipolar interactions of these new dyes were investigated by UV–vis absorption, fluorescence spectroscopy, electrostatic potential and frontier molecular orbital calculations as well as electrochemical cyclic voltammetry measurements. Two pyrene-based dyes can be mutually transformed by reversible formation or cleavage of Diels-Alder covalent bonds through click/declick reaction. During the reversible reaction, switchable fluorescence ON/OFF behaviors were interestingly observed. X-ray single crystal diffraction revealed that supramolecular donor/acceptor dipolar and π-π stacking interactions work cooperatively to form stronger interaction and the shorter distance (3.38 ?) between donor and acceptor than general π-π stacking distance (3.54 ?). An amphiphilic dye is self-assembled in water into blue fluorescent, hollow vesicular aggregates with the average diameter of 115–120 nm and a narrow size distribution as revealed by dynamic light scattering, scanning electron microscopy and transmission electron microscopy.
NEUROACTIVE STEROIDS AND COMPOSITIONS AND METHODS THEREOF
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Paragraph 00227; 00230, (2021/06/11)
The invention provides novel neuroactive steroids and pharmaceutical compositions thereof, as well as methods of their preparation and use, in therapy of various diseases and conditions, for example, various neurological or brain diseases.
Synthesis of Pd Complexes Containing Tailed NHC Ligands and Their Use in a Semicontinuous Membrane-Assisted Suzuki Cross-Coupling Process
Ormerod, Dominic,Dorbec, Matthieu,Merkul, Eugen,Kaval, Nadya,Lefèvre, Nicolas,Hostyn, Steven,Eykens, Lies,Lievens, Jo,Sergeyev, Sergey,Maes, Bert U. W.
supporting information, p. 1509 - 1517 (2018/10/25)
Homogeneous catalysis has proved to be a reliable method for preparing numerous molecular entities, but catalysts can be expensive and difficult to remove. Because of this, industry targets catalysts that are easily separated and recovered and feature increased turnover numbers. The ongoing shift from multipurpose batch reactors toward continuous manufacturing in fine chemicals synthesis results in a new set of catalyst requirements. This paper reports the design and use of Pd complexes suitable for a semicontinuous Suzuki cross-coupling reaction based on a membrane-assisted reactor. These Pd complexes contain tailed N-heterocyclic carbene (NHC) ligands, allowing internal catalyst recovery by organic solvent nanofiltration with top-layer-modified ceramic membranes. These membranes give selective nanofiltration of the catalyst based on a combination of size exclusion and affinity separation (solvent-solute-membrane interactions). The semicontinuous system developed led to significantly improved turnover numbers, simplified product isolation, and consequently reduced mass intensity by simply adding more of the reactants and reagents to the reaction vessel.
