Application of 2-(3,5,6-Trifluoro-2-hydroxy-4-methoxyphenyl)benzoxazole and -benzothiazole to Fluorescent Probes Sensing pH and Metal Cations
摘要:
2-(3,5,6-Trifluoro-2-hydroxy-4-methoxyphenyl)benzoxazole (3) and benzothiazole analogue (4) are prepared by the two-step procedures from the corresponding 2-(pentafluorophenyl)benzazoles. Benzoxazole 3 is applicable to a fluorescent probe sensing magnesium cation, and 4 is suitable for sensing zinc cation. Both fluorophores 3 and 4 are sensitive to the pH change at pH 7-8, resulting in large fluorescence enhancement under basic conditions. Their high sensitivity to pH and selectivity in metal cations are ascribed to the high acidity of the fluorophenol moiety.
with various substituted benzoic acids is developed. The reaction is compatible with both electron-rich and electron-poor benzoic acids. It can also be extended to the synthesis of polyfluoro-substituted biaryls using polyfluorobenzenes as the starting materials.
Copper mediated decarboxylative direct C–H arylation of heteroarenes with benzoic acids
作者:Tuhin Patra、Sudip Nandi、Santosh K. Sahoo、Debabrata Maiti
DOI:10.1039/c5cc08367b
日期:——
Decarboxylative coupling reactions till date required stoichiometric oxidant (such as copper and silver salts) for decarboxylation purpose along with a metal catalyst (e.g. palladium) for cross coupling. In this communication,...
Prenyl Praxis: A Method for Direct Photocatalytic Defluoroprenylation
作者:Sonal Priya、Jimmie D. Weaver
DOI:10.1021/jacs.8b09156
日期:2018.11.28
method that provides access to "hybrid molecules" that possess both the functionality of a prenyl group and fluorinated arenes. This approach involves direct prenyl group transfer under very mild conditions, displays excellent functional group tolerance, and includes relatively short reaction times (<4 h), which is the fastest photocatalytic C-F functionalization developed to date. Additionally, the
PdF: A simple catalytic system, broad substrate scope, and high versatility provide a useful and facileaccess to partiallyfluorinatedaromatics (see scheme). Tuning the reaction conditions enables a diverse range of product structures to be prepared.