395-48-2Relevant articles and documents
Regioselective C-H Trifluoromethylation of Aromatic Compounds by Inclusion in Cyclodextrins
Lu, Xu,Kawazu, Ryohei,Song, Jizhou,Yoshigoe, Yusuke,Torigoe, Takeru,Kuninobu, Yoichiro
supporting information, p. 4327 - 4331 (2021/05/26)
A regioselective radical C-H trifluoromethylation of aromatic compounds was developed using cyclodextrins (CDs) as additives. The C-H trifluoromethylation proceeded with high regioselectivity to afford the product in good yield, even on the gram scale. In the presence of CDs, some substrates underwent a single trifluoromethylation selectively, whereas mixtures of single- and double-trifluoromethylated products were formed in the absence of the CD. 1H NMR experiments indicated that the regioselectivity was controlled by the inclusion of a substrate inside the CD cavity.
Ligand-free Cu(ii)-catalyzed aerobic etherification of aryl halides with silanes: An experimental and theoretical approach
Ahmed, Muhammad Naeem,Ahmad, Khalil,Yasin, Khawaja Ansar,Farooq, Tayyaba,Khan, Bilal Ahmad,Roy, Soumendra K.
, p. 11316 - 11333 (2019/07/31)
Owing to their wide occurrence in nature and immense applications in various fields, the synthesis of aryl alkyl ethers has remained a focus of interest. In contrast to the conventional/traditional methods of etherification, herein, we have reported a more efficient method, which is better yielding and more general in application. The etherification of aryl halides by alkoxy/phenoxy silanes was catalyzed by copper acetate in the presence of cesium carbonate and oxygen in DMF at 145 °C. All the as-synthesized compounds were characterized via the 1H-NMR and 13C-NMR spectroscopic techniques. Density functional theory calculations using the B3LYP functional were performed to elucidate the reaction mechanism. The C-O coupling reaction between 2-nitroiodobenzene and tetramethoxysilane was used as a model reaction. The activation energy barriers for the generation of catalytic species (31.6 kcal mol-1) and the σ-bond metathesis (16.0 kcal mol-1), oxidative addition/reductive elimination (20.3 kcal mol-1), halogen atom transfer (19.2 kcal mol-1) and single electron transfer (SET) (29.5 kcal mol-1) mechanisms for the C-O coupling reaction were calculated. Calculations for the key reaction steps were repeated with the B3PW91, PBEH1PBE, wB97XD, CAM-B3LYP and mPW1LYP functionals. The formation of catalytic species via a single electron transfer reaction between tetramethoxysilane and copper acetate, formation of methoxy radicals and methoxylation of copper showed an overall energy barrier of 31.6 kcal mol-1, and therefore is the rate determining step.
Phosphovanadomolybdic acid catalyzed direct C-H trifluoromethylation of (hetero)arenes using NaSO2CF3 as the CF3 source and O2 as the terminal oxidant
Li, Chifeng,Suzuki, Kosuke,Yamaguchi, Kazuya,Mizuno, Noritaka
supporting information, p. 1417 - 1420 (2017/02/23)
A direct C-H trifluoromethylation of (hetero)arenes using NaSO2CF3 (Langlois' reagent) as the CF3 source and O2 as the terminal oxidant has been developed. In the presence of catalytic amounts of phosphovanadomolybdic acids, such as H6PV3Mo9O40, various kinds of substituted benzenes and heteroaromatic compounds could be converted into the corresponding trifluoromethylated products.
