10.1002/1521-3765(20010216)7:4<903::AID-CHEM903>3.0.CO;2-M
The research focuses on the synthesis of difluoro-C-glycosides and difluoro-C-disaccharides through the reactions of difluoroenoxysilanes with glycosyl donors, such as acylglycosides and glycals. The study explores the influence of the substituent in the 2-position of the glycosyl donor on the reaction's regioselectivity and stereoselectivity. Key reactants include acylsilanes, trifluoromethyltrimethylsilane (TFMTMS), and various glycosyl donors. The methodology involves the preparation of difluoroenoxysilanes from acylsilanes and TFMTMS under fluoride activation, followed by glycosylation with glycosyl donors. Analyses used to characterize the products include nuclear magnetic resonance (NMR) spectroscopy, infrared (IR) spectroscopy, mass spectrometry (MS), and elemental analysis. The research also discusses the potential of these compounds as non-hydrolyzable glycoside mimics and their biochemical properties.
10.1016/j.tet.2015.08.016
The study presents a direct and efficient method for the trifluoromethylation and pentafluoroethylation of 1,1-diaryl-2,2-difluoroethenes using TMSCF3 and TMSCF2CF3, respectively, in the presence of TBAF as a fluoride source, without the need for metal catalysts. The reactions were conducted under mild conditions and yielded a variety of monotrifluoromethylated, bistrifluoromethylated, monopentafluoroethylated, and bispentafluoroethylated products in fair to good yields. The chemicals used in the study include TMSCF3 (known as Ruppert-Prakash reagent), TMSCF2CF3, TBAF, and various 1,1-diaryl-2,2-difluoroethenes. These chemicals served the purpose of enabling the synthesis of complex organic molecules with fluorinated alkene structures, which are valuable in pharmaceuticals, agrochemicals, and material science due to their unique properties.
10.1021/ja00183a073
The study investigates the reactivity of the metal-oxo complex CP*~W=O, exploring its interactions with various substances. The complex undergoes 1,2-additions with both polar and nonpolar u bonds, such as H-H and H-SiMe3, leading to the formation of different tungsten derivatives. It also reacts with oxidizing agents like H2O2 and Me3CO2H, resulting in oxygen atom transfer and the formation of dioxo tungsten derivatives. Notably, the complex reacts with O2, leading to the insertion of an oxygen atom from O2 into a W-($-C,Me,) bond, forming (T$-C,M~,)W(=O),- (OC,Me,). The study highlights the potential of organotungsten derivatives in catalytic oxidation reactions. Additionally, the study explores the use of trifluoromethyltrimethylsilane (TMS-CF3) as a nucleophilic trifluoromethylating agent for carbonyl compounds, catalyzed by fluoride ions, resulting in the formation of trifluoromethylated siloxy adducts which can be hydrolyzed to alcohols.
10.1021/acs.orglett.1c01720
The study presents an efficient method for the trifluoromethylation of benzoic acids using TMSCF3 (trimethylsilyl trifluoromethane) to produce aryl trifluoromethyl ketones. The reaction involves anhydrides as in situ activating reagents, with trifluoroacetic anhydride (TFAA) and 4-dimethylaminopyridine (DMAP) playing crucial roles in activating the carboxylic acids and facilitating nucleophilic addition. CsF (cesium fluoride) is used to enhance the yield of the desired products. The reaction is conducted in PhOMe (anisole) solvent under nitrogen at 120 °C for 15 hours. The study demonstrates a wide substrate scope, including various carboxylic acids with different functional groups, and shows high functional group tolerance. Notably, bioactive molecules such as adapalin, probenecid, and telmisartan can also be trifluoromethylated using this method, highlighting its potential in drug design and development. The reaction conditions are relatively mild, and the process is scalable, making it a practical and environmentally benign approach for synthesizing aryl trifluoromethyl ketones.