The synthesis of several 1,1-disubstituted trifluoromethyl-cyclopropanes (TFCPs), known as tert-butyl bioisosteres, has been achieved from the reaction between trifluoromethylalkenes and unstabilized sulfonium ylides in yields of ≤97%. This method offers practical access to this cyclopropyl moiety of pharmacological interest, employing a commercially available reagent at low temperatures. The synthesis
by lithiation of 2-bromo-3,3,3-trifluoroprop-1-ene and successively underwent borylation in a flow microreactor system. Direct use of the 1-(trifluoromethyl)vinylborate thus formed for the Suzuki–Miyaura coupling in a batch system afforded α-(trifluoromethyl)styrenes in high yields.
Synthesis of Trifluoromethylated Aziridines Via Photocatalytic Amination Reaction
作者:Yujing Guo、Chao Pei、Sripati Jana、Rene M. Koenigs
DOI:10.1021/acscatal.0c04564
日期:2021.1.1
catalyst and release a nitrene radical anion, which serves as a reactive intermediate in direct aziridination reactions of fluorinated olefins. We have demonstrated the applicability of this photocatalytic synthesis platform to accessfluorinated aziridines in a generalized fashion, allowing for different substitution patterns of the fluorinated aziridine core, including difluoromethyl and perfluoroalkylated
A Chiral Pentafluorinated Isopropyl Group via Iodine(I)/(III) Catalysis
作者:Stephanie Meyer、Joel Häfliger、Michael Schäfer、John J. Molloy、Constantin G. Daniliuc、Ryan Gilmour
DOI:10.1002/anie.202015946
日期:2021.3.15
catalysis strategy to construct an enantioenriched fluorinated isostere of the iPr group is reported. The difluorination of readily accessible α‐CF3‐styrenes is enabled by the in situ generation of a chiral ArIF2 species to forge a stereocentre with the substituents F, CH2F and CF3 (up to 95 %, >20:1 vicinal:geminal difluorination). The replacement of the metabolically labile benzylic proton results
报道了构建 Pr 基团的对映体富集氟化等排体的 I(I)/(III) 催化策略。通过原位生成手性 ArIF 2物质,可实现易于接近的 α-CF 3 -苯乙烯的二氟化,从而与取代基 F、CH 2 F 和 CF 3形成立构中心(高达 95 %,>20:1邻位) :偕二氟化)。通过X射线晶体学(π→σ*和立体电子gauche σ→σ*相互作用)确定,代谢不稳定的苄基质子的替代产生了高度预组织的支架。公开了一种催化剂编辑方法,其中对映选择性的初步验证是建立在结构基础上的。
Regio‐ and Enantioselective Intermolecular Aminofluorination of Alkenes via Iodine(I)/Iodine(III) Catalysis**
作者:Michael Schäfer、Timo Stünkel、Constantin G. Daniliuc、Ryan Gilmour
DOI:10.1002/anie.202205508
日期:2022.8.8
The regio- and enantioselective, intermolecular vicinal fluoroamination of α-trifluoromethyl styrenes was achieved by enantioselective II/IIII catalysis. The transient iodonium intermediate is intercepted with nitriles, which function as both the solvent and nucleophile. In situ Ritter reaction provides direct access to the corresponding amides (up to 89 % yield). Crystallographic analyses of the β-fluoroamide