Construction of β-Trifluoromethyl Enol Ether via Base-Promoted C-O Coupling and Rearrangement of Hydrogen Atom

Synthesis of aryl 2-bromo-2-chloro-1,1-difluoroethyl ethers through the base-mediated reaction between phenols and halothane

An efficient and convenient method for the synthesis of structurally unique and highly functionalized aryl 2-bromo-2-chloro-1,1-difluoroethyl ethers has been developed. This approach exhibits a broad reaction scope, a simple operation and without the need of any expensive transition-metal catalyst, highly toxic or corrosive reagents. Notably, we demonstrate the potential utility of halothane for the synthesis of aryl gem-difluoroalkyl ethers containing the bromochloromethyl group.

Metal-free catalytic hydrocarboxylation of hexafluorobut-2-yne

An efficient method for stereoselective synthesis of trifluorinated enol esters catalyzed by base was introduced.

Applications of 2-Chloro-3,3,3-trifluoroprop-1-ene (HCFO-1233xf): A Rapid Entry to Various β-Substituted-trifluoromethyl-ethenes

An efficient base-promoted reaction of O-, N-, and S-nucleophiles with 2-chloro-3,3,3-trifluoprop-1-ene (HCFO-1233xf) is described providing access to various β-substituted-trifluoromethyl-ethenes under mild reaction conditions. Mechanistic investigations shed some light on the regio-, chemo-, and stereoselectivities observed. The olefins prepared represent attractive intermediates in chemical discovery: some applications include their conversion to pyrrolidines via a [3 + 2] dipolar cycloaddition reaction. These weakly basic amines represent novel synthons that could be readily elaborated through a range of reactions.

Insight into the Intermolecular Interaction and Free Radical Polymerizability of Methacrylates in Supercritical Carbon Dioxide

High pressure in situ Fourier transfer infrared/near infrared technology (HP FTIR/NIR) along with theoretical calculation of density functional theory (DFT) method was employed. The solvation behaviors and the free radical homopolymerization of methyl methacrylate (MMA), methacrylate acid (MAA), trifluoromethyl methacrylate (MTFMA) and trifluoromethyl methacrylate acid (TFMAA) in scCO2 were systematically investigated. Interestingly, the previously proposed mechanism of intermolecular-interaction dynamically-induced solvation effect (IDISE) of monomer in scCO2 is expected to be well verified/corroborated in view that the predicted solubility order of the monomers in scCO2 via DFT calculation is ideally consistent with that observed via HP FTIR/NIR. It is shown that MMA and MAA can be easily polymerized, while the free radical polymerizability of MTFMA is considerably poor and TFMAA cannot be polymerized via the free radical initiators. The α trifluoromethyl group (-CF3) may effectively enhance the intermolecular hydrogen bonding and restrain the diffusion of the monomer in scCO2. More importantly, the strong electron-withdrawing inductive effect of -CF3 to C=C may distinctly decrease the atomic charge of the carbon atom in the methylene (=CH2). These two factors are believed to be predominantly responsible for the significant decline of the free radical polymerizability of MTFMA and the other alkyl 2-trifluoromethacrylates in scCO2.