653-39-4Relevant articles and documents
Some Comments on a Recently Proposed Method of Determining Chlormequat Residues by Derivatization With Pentafluorothiophenol
Mortimer, Richard D.,Weber, Dorcas F.
, p. 31 - 36 (1994)
A recent publication concerning the analysis of residues of the herbicide chloromequat in cotton seed by gas chromatography contains a significant error. A derivative prepared by reacting pentafluorothiophenol with chlormequat is actually produced by the reaction of the initial product of demethylation of chlormequat with a second molecule of pentafluorothiophenol. As the derivative in not derived from the chlormequat backbone, the method is not specific to chlormequat and could be misleading to an analyst using it or adapting it to other produce.
Mild C?F Activation in Perfluorinated Arenes through Photosensitized Insertion of Isonitriles at 350 nm
Weidlich, Frauke,Esumi, Naoto,Chen, Dongyang,Mück-Lichtenfeld, Christian,Zysman-Colman, Eli,Studer, Armido
supporting information, p. 376 - 383 (2019/11/19)
Fluorinated compounds have become important in the fields of agrochemical industry, pharmaceutical chemistry and materials sciences. Accordingly, various methods for their preparation have been developed in the past. Fluorinated compounds can be accessed via conjugation with fluorinated building blocks, via C?H fluorination or via selective activation of perfluorinated compounds to give the partially fluorinated congeners. Especially the direct activation of C?F bonds, one of the strongest σ-bonds, still remains challenging and new strategies for C?F activation are desirable. Herein a method for the photochemical activation of aromatic C?F bonds is presented. It is shown that isonitriles selectively insert into aromatic C?F bonds while aliphatic C?F bonds remain unaffected. Mechanistic studies reveal the reaction to proceed via the indirect excitation of the isonitrile to its triplet state by photoexcited acetophenone at 350 nm. Due to the relatively mild light used, the process shows high functional group tolerance and various compounds of the class of benzimidoyl fluorides are accessible from aryl isonitriles and commercially available perfluorinated arenes. (Figure presented.).
Synthesis of the farnesyl ether 2,3,5-trifluoro-6-hydroxy-4-[(E,E)-3,7,11-trimethyldodeca-2,6,10-trien-1-yloxy] nitrobenzene, and related compounds containing a substituted hydroxytrifluorophenyl residue: Novel inhibitors of protein farnesyltransferase, geranylgeranyltransferase I and squalene synthase
Marriott, Jonathan H.,Moreno Barber, Amelia M.,Hardcastle, Ian R.,Rowlands, Martin G.,Grimshaw, Rachel M.,Neidle, Stephen,Jarman, Michael
, p. 4265 - 4278 (2007/10/03)
Pentafluoronitrobenzene was converted via two successive phase-transfer catalysed SNAr reactions with (E,E)-farnesol or geraniol followed by hydroxide ion into the 2,3,6-trifluoro-5-hydroxy-4-nitrophenyl farnesyl ether 3a and the geranyl ether 3b. Analogues containing a cyano (3c) or carbamoyl (3d) group in place of nitro or an epoxygeranyl (3e) group as the prenyl (3-methylbut-2-enyl) containing residue were similarly prepared. Those containing a sulfonic acid (35a, 35b) or a methyl sulfone (41) group were made by modifications of this approach involving the use of protecting groups. The synthesis of carboxy analogues (27a, 27b) involved the alkylation of a protected fluorinated ortho-hydroxybenzoic acid derivative (25) with (E,E)-farnesyl or geranyl bromide. The non-fluorinated compound 18 was analogously prepared via compound 17a. Mitsunobu reactions were used in the synthesis of 15, a dihydroxylated analogue of 3b, and of 8, the non-fluorinated analogue of 3a. The nitro compounds 3a and 3b were moderate inhibitors of both farnesyl transferase and geranylgeranyl transferase I, the geranyl carboxy derivative 27b of the latter enzyme and the farnesyl sulfonic acid derivative 35a of squalene synthase. The Royal Society of Chemistry 2000.
