2613-30-1Relevant articles and documents
Di- and Trifluorinated 2-Azidobenzimidazole Derivatives: Synthesis, Photooxygenation, and 19F NMR Prediction
Kanitz, Nils E.,Fresia, Marvin,Jones, Peter G.,Lindel, Thomas
, p. 3573 - 3578 (2021/07/22)
The photoreactivity of a series of hitherto unknown, multiply fluorinated 2-azidobenzimidazole derivatives was investigated. The synthesis of the starting material includes regioselective p-defluorination of nitrobenzene derivatives employing Ogoshi's conditions. If the 6-position was unsubstituted, irradiation in the presence of N-protected amino acids at 300 nm (Rayonet) led to the formation of arylesters by oxygenation of the 6-position in good to excellent yields and perfect regioselectivity. We did not observe any displacement of fluoride. If the 6-position itself was fluorinated, alternative positions of the benzene portion were attacked. Mechanistically, the reaction proceeds through ring opening of the singlet nitrene to the cyanodiimine or via the iminobenzimidazolium ion. The availability of a set of fluorinated photo-adducts prompted the quantum chemical calculation of their 19F NMR chemical shifts. Even with the most suitable method investigated (ωB97XD/TApr-cc-pVDZ), deviations of up to 5 ppm from the experimental values were observed, underlining the importance of experimental measurements.
2-SUBSTITUTED-6-AMINO-5-ALKYL, ALKENYL OR ALKYNYL-4-PYRIMIDINECARBOXYLIC ACIDS AND 6-SUBSTITUTED-4-AMINO-3- ALKYL, ALKENYL OR ALKYNYL PICOLINIC ACIDS AND THEIR USE AS HERBICIDES
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Page/Page column 7-8, (2009/04/24)
6-Amino-4-pyrimidinecarboxylic acids having alkyl, alkenyl or alkynyl substituents in the 5-position and 4-aminopicolinic acids having alkyl, alkenyl or alkynyl substituents in the 3-position, and their amine and acid derivatives, are potent herbicides demonstrating a broad spectrum of weed control.
Electrophilic aromatic fluorination with fluorine: meta-Directed fluorination of anilines
Alric,Marquet,Billard,Langlois
, p. 661 - 667 (2007/10/03)
Anilines are mainly or selectively fluorinated in the meta-position with F2 when dissolved in triflic acid, sometimes in the presence of small quantities of antimony pentafluoride. The regioselectivity is increased when an electron-donating substituent is present at the para-position.