The trifluoromethylation of benzoic acids with TMSCF3 was achieved through nucleophilic substitution with the use of anhydrides as an in situ activating reagent. Under the reaction conditions, a wide range of carboxylic acids including the bioactive ones worked well, thus providing a facile and efficient method for preparing aryl trifluoromethyl ketones from the readily available starting materials
Enantioselective Palladium-Catalyzed [3+2] Cycloaddition of Trimethylenemethane and Fluorinated Ketones
作者:Barry M. Trost、Guillaume Mata
DOI:10.1002/anie.201807308
日期:2018.9.17
undergoes palladium‐catalyzed [3+2] cycloadditions with fluorinated ketones to generate tetrasubstituted trifluoromethylated centers in high enantioselectivity under mild conditions. The generation of the palladium–TMM complex was achieved by a self‐deprotonation strategy, which shows remarkable improvements in regiocontrol, efficiency, and atom economy of asymmetric [3+2] cycloadditions. Moreover, the
Chemoselective Trifluoromethylation of Methyl Esters Using an Et<sub>3</sub>GeNa/C<sub>6</sub>H<sub>5</sub>SCF<sub>3</sub> Combination: Efficient Synthesis of Trifluoromethyl Ketones
作者:Yasuo Yokoyama、Kunio Mochida
DOI:10.1055/s-1997-961
日期:1997.8
Various trifluoromethyl ketones were synthesized from the corresponding methyl esters by effective nucleophilic trifluoromethylation using an Et3GeNa/C6H5SCF3 combination. This trifluoromethylation proceeded chemoselectively. When, cyclohexyl, i-propyl and t-butyl esters coexisted in the reaction system, only the methyl ester was easily transformed to the desired compounds in excellent yield. Furthermore, some protective groups were remained under this reaction condition.
An enantioselective hydroxyalkylation of indoles and 7‐azaindole with trifluoromethyl ketones was found to be effectively promoted under high‐pressure conditions with a low loading of Cinchona alkaloids (e.g., 1–3 mol% of cinchonidine). Chiral tertiary alcohols containing a trifluoromethyl group were obtained at 9 kbar with good yield and enantioselectivity up to 89%, whereas usually merely traces
Catalytic Asymmetric Reduction of α-Trifluoromethylated Imines with Catecholborane by BINOL-Derived Boro-phosphates
作者:Hualing He、Xiaoxue Tang、Yang Cao、Jon C. Antilla
DOI:10.1021/acs.joc.0c03009
日期:2021.3.5
A catalytic enantioselective reduction of α-trifluoromethylated imines by a BINOL-derived boro-phosphate employing catecholborane as hydride source has been developed. This method provides an efficient route to prepare synthetically useful chiral α-trifluoromethylated amines in high yields and with excellent enantioselectivities (up to 98% yield and 96% ee) under mild conditions.