A Convenient Route to Tetraalkylammonium Perfluoroalkoxides from Hydrofluoroethers

Abstract

Hydrofluoroethers are shown to alkylate tertiary amines readily under solvent-free conditions, affording valuable tetraalkylammonium perfluoroalkoxides bearing a-fluorines. The reaction of R F CF 2 ÀOCH 3 (R F = CF 2 CF 3 , CF 2 CF 2 CF 3 , and CF(CF 3 ) 2 ) with NR 1 R 2 R 3 produces twenty new a-perfluoroalkoxides, [(CH 3 )NR 1 R 2 R 3 ][R F CF 2 O] under mild conditions. These a-perfluoroalkoxides are easy to handle, thermally stable, and can be used for the perfluoroalkoxylation of benzyl bromides. Scheme 1. Elimination of fluoride from a-perfluoroalkoxides.

The Origin of Li-O2Battery Performance Enhancement Using Fluorocarbon Additive

“…of different compounds containing -CO 3, C-O, C=O, O-C-O, O-F, Cl-O, Cl-Li, and hydrocarbon bonds on the samples discharged in DME and DME+1-PFC, which suggests that the electrolyte solvent and salt decomposed partially to form these species. 21,22 Even though we could not observe the presence of Li 2 O 2 from XPS spectra, we believe that Li 2 O 2 may have formed and decomposed. In fact, our previous results using a very similar system in DME and TEGDME showed the presence of Li 2 O 2 conclusively.…”

“…The 19 F and 1 H NMR peaks for 1-PFC are consistent with the literature. 22 The peaks associated to 1-PFC completely disappear upon discharge at 100 mAg −1 C up to 2 V for both 19 F and 1 H NMR. This clearly shows that the 1-PFC is unstable during discharge, possibly due to reactions with the superoxide species on the electrode and/or in the solutions.…”

Radical Trifluoromethoxylation of Arenes Triggered by a Visible‐Light‐Mediated N−O Bond Redox Fragmentation

“…[3] Progress has largely been impeded by the low reactivity of anionic OCF 3 , the propensity for b-fluoride elimination in classic transitionmetal-mediated cross-couplings,and the ensuing complicated procedures for the generation of C(sp 2 )ÀOCF 3 or OÀCF 3 ether bonds. [4] Thus the synthesis of complex molecules containing an OCF 3 substituent has been relegated to commercially available but costly building blocks in unidirectional, multistep syntheses. [3,5] Although substantial advances were made by Ritter in his seminal paper in 2011, [6] which have since been complemented by Ngai, [7] Qing, [8] Tang, [9] and Liu, [10] no practical method has been developed to access this privileged class of ethers (Scheme 1).…”