Synthesis of benzo[1,2-b:4,5-b′]difuran derivatives utilizing concomitant photocyclization and photo-Fries rearrangement reactions

Ligand-controlled regiodivergent π-allyl palladium catalysis enables a switch between [3+2] and [3+3] cycloadditions

Reported herein is the use of ligands to tune the regioselectivity and reactivity of palladium-catalyzed [3+2] and [3+3] cycloadditions.

Synthesis, structural properties, electrophilic substitution reactions and DFT computational studies of calix[3]benzofurans

Synthesis of highly flexible calix[3]benzofurans; effects of substituent groups on calix[3]benzofuran conformations were studied by DFT computational methods.

Direct and indirect photolysis of cyhalofop in aqueous systems

The photodegradation of the aryloxyphenoxy propionic herbicide cyhalofop-butyl (2R)-2-[4-(4-cyano-2-fluorophenoxy)phenoxy]butylpropanoate (CyB), and of its primary metabolite (2R)-2-[4-(4-cyano-2-fluorophenoxy)phenoxy]propanoic acid (CyA) was studied in water at different irradiation wavelengths. The sunlight irradiation was investigated also in the presence of humic acid (HA), Fe oxide, titanium dioxide (TiO2) and zinc oxide (ZnO) as photocatalysts. CyB and CyA were rapidly degraded by UV irradiation. CyB afforded the butyl ester of 2-[3-(4-cyano-2-fluorophenyl)-4-hydroxy-phenoxy]propanoic acid (CyI), a metabolite arising from a photo-Fries rearrangement. Instead, CyA yielded (R)-2-4-(4-carboxyl-2-fluorophenoxy)phenoxypropanoic acid (CyD), a dicarboxylic acid arising from the photo-hydrolysis of cyano group via amide. CyB was stable in simulated sunlight also in the presence of the catalysts tested. The irradiation of a CyA solution, in the presence of HA or Fe oxide, with simulated sunlight did not produce any significant degradation. In the same experimental conditions, CyA was totally mineralized in the presence of TiO2 and ZnO.