115706-17-7Relevant articles and documents
Site-Selective Cross-Coupling of Remote Chlorides Enabled by Electrostatically Directed Palladium Catalysis
Golding, William A.,Pearce-Higgins, Robert,Phipps, Robert J.
supporting information, p. 13570 - 13574 (2018/10/20)
Control of site-selectivity in chemical reactions that occur remote from existing functionality remains a major challenge in synthetic chemistry. We describe a strategy that enables three of the most commonly used cross-coupling processes to occur with high site-selectivity on dichloroarenes that bear acidic functional groups. We have achieved this by repurposing an established sulfonylated phosphine ligand to exploit its inherent bifunctionality. Mechanistic studies suggest that the sulfonate group engages in attractive electrostatic interactions with the cation associated with the deprotonated substrate, guiding cross-coupling to the chloride at the arene meta position. This counterintuitive combination of anionic ligand and anionic substrate demonstrates an alternative design principle when considering the application of noncovalent interactions to direct catalysis.
Iron(III)-Catalyzed Ortho-Preferred Radical Nucleophilic Alkylation of Electron-Deficient Arenes
Yu, Fei,Wang, Ting,Zhou, Huan,Li, Yajun,Zhang, Xinhao,Bao, Hongli
supporting information, p. 6538 - 6541 (2017/12/26)
The untraditional iron-catalyzed, ortho-preferred, radical alkylation of electron-deficient (hetero)arenes is reported. A variety of electron-deficient arenes were shown to react with various primary alkyl sources, producing the alkylated (hetero)arenes in good yields. This reaction might be an alkyl radical, nucleophilic aromatic substitution reaction, rather than the traditional electrophilic Friedel-Crafts reaction. HOMO-LUMO analysis and DFT studies on the key transition states underlying the regioselectivity are consistent with the observed reactions and the conclusions.
Structure-activity relationships of phenylpropanoids as antifeedants for the pine weevil Hylobius abietis
Bohman,Nordlander,Nordenhem,Sunnerheim,Borg-Karlson,Unelius
, p. 339 - 352 (2008/09/18)
Ethyl cinnamate has been isolated from the bark of Pinus contorta in the search for antifeedants for the pine weevil, Hylobius abietis. Based on this lead compound, a number of structurally related compounds were synthesized and tested. The usability of the Topliss scheme, a flow diagram previously used in numerous structure-activity relationship (SAR) studies, was evaluated in an attempt to find the most potent antifeedants. The scheme was initially followed stepwise; subsequently, all compounds found in the scheme were compared. In total, 51 phenylpropanoids were tested and analyzed for SARs by using arguments from the field of medicinal chemistry (rational drug design). Individual Hansch parameters based on hydrophobicity, steric, and electronic properties were examined. The effects of position and numbers of substituents on the aromatic ring, the effects of conjugation in the molecules, and the effects of the properties of the parent alcohol part of the esters were also evaluated. It proved difficult to find strong SARs derived from single physicochemical descriptors, but our study led to numerous new, potent, phenylpropanoid antifeedants for the pine weevil. Among the most potent were methyl 3-phenylpropanoates monosubstituted with chloro, fluoro, or methyl groups and the 3,4-dichlorinated methyl 3-phenylpropanoate.
