4681-17-8Relevant articles and documents
Systematic Variation of Ligand and Cation Parameters Enables Site-Selective C-C and C-N Cross-Coupling of Multiply Chlorinated Arenes through Substrate-Ligand Electrostatic Interactions
Golding, William A.,Schmitt, Hendrik L.,Phipps, Robert J.
, p. 21891 - 21898 (2021/01/11)
Use of attractive noncovalent interactions between ligand and substrate is an emerging strategy for controlling positional selectivity. A key question relates to whether fine control on molecules with multiple, closely spaced reactive positions is achievable using typically less directional electrostatic interactions. Herein, we apply a 10-piece "toolkit"comprising of two closely related sulfonated phosphine ligands and five bases, each possessing varying cation size, to the challenge of site-selective cross-coupling of multiply chlorinated arenes. The fine tuning provided by these ligand/base combinations is effective for Suzuki-Miyaura coupling and Buchwald-Hartwig coupling on a range of isomeric dichlorinated and trichlorinated arenes, substrates that would produce intractable mixtures when typical ligands are used. This study develops a practical solution for site-selective cross-coupling to generate complex, highly substituted arenes.
Herbicidal 3-(substituted-benzyl)-1-methyl-6-trifluoromethyluracils
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, (2008/06/13)
Herbicidal 3-(substituted-benzyl)-1-methyl-6-trifluoromethyluracils, compositions containing them, and methods of using them to control undesired plant growth, including use to control weeds in certain crops, are disclosed. The herbicidal compounds of the present invention are defined by the following generic structure: STR1 in which V is hydrogen or halogen; W is hydrogen, halogen, lower alkoxy, lower alkylaminocarbonyl, propargyloxy, or cyano; X is hydrogen or chlorine; and Y is hydrogen, halogen, cyano, lower alkylaminocarbonyl, or carboxy.