To achieve highly conductive polymer electrolytes with a controllable ionic transference number, a novel polymeric lithium salt was synthesized and characterized. The novel lithium salt of a perfluorinated polyimide anion, poly(5-oxo-3-oxy-4-trifluoromethyl-1,2,4-pentafluoropentylene sulfonylimide lithium) (LiPPI), has a polyanionic backbone with a repeating unit resembling highly dissociable, thermally and electrochemically stable imide salts, such as lithium bis(trifluoromethylsulfonyl)imide (LiTFSI). The ion-conductive behavior of LiPPI in an organic solvent and in a polyether was extensively studied by using pulse-gradient spin-echo NMR, in addition to differential scanning calorimetry, complex impedance measurement, and dynamic mechanical analysis. Solutions of LiPPI in ethylene carbonate (EC) exhibited a high degree of dissociation and high ionic conductivity, and the self-diffusion coefficient of the anion was lower than that of the cation. Solvent-free polymer electrolytes were prepared by dissolving LiPPI in a matrix polyether to afford a compatible polymer alloy, and the ionic conductivity of the new polymer alloy electrolytes reached ca. 10-5 S cm-1 at 30 °C. Although the lithium ionic transference number in the organic electrolyte solution was approximately the same as that of LiTFSI in EC, the polymer alloy electrolyte gave an apparent transference number higher than 0.7, which was considerably higher than that of LiTFSI in the same polyether.
It is shown that a-phenylsulphinylacrylate derivatives undergo three modes of rearrangement reactions induced selectively by the agent used. On treatment with an acidic reagent (hot dioxan-dilute sulphuric acid or acetic anhydride) a vinylogous-type Pummerer rearrangement takes place to produce the y-hydroxylated or -acetoxylated phenylthio-derivatives, while under basic condition (pyridine-water or -acetic anhydride) a sequential prototropic shift and allylic sulphoxide-sulphenate rearrangement occurs regioselectively to give the sulphur-free y -hydroxy or -acetoxy acrylates. When a highly nucleophilic agent (acetyl chloride, trifluoroacetic anhydride, or thionyl chloride) is used, the ap-difunctionalised a-phenylthio-ester derivatives are formed through the third mode of rearrangement, an additive-type Pummerer reaction. THE transformation of sulphoxides into a-acetoxy sulphides, induced by hot acetic anhydride, is the well known Yummerer rearrangement ,1-3 although Parham and Edwards reported that simple vinyl sulphoxides, such as 2-methyl-3-( phenylsulphinyl)but-2-ene and 1-(phenylsulphiny1)cycloliexene are stable to hot acetic anhydride. However, other types of rearrangement reactions involving the migration of a p-hydrogen or a sulphide group were recently reported for styryl sulphoxides 3 9 4 and p-aminovinyl sulphoxides.5 Additional examples of unusual rearrangements were observed in the reaction of phenyl vinyl sulphoxide with dithioacetic acid,6 and in the reaction of the cyclic vinyl sulphoxides, 1,4-thiazine l-oxides.'In this paper we describe three modes of rearrangement of the a-phenylsulphinylacrylate derivatives (1 ) (Scheme 0 / OR SCHEME 1 The thrce rearrangements o f cr-phenylsulpliiii~l-acrylates (a) acidic reagcnts; (b) basic reagents; (c) highly nucleophilic reagents 1) : (a) the vinylogous Pummerer (acid-induced, weak nucleophile) ; 8 (b) the sequential prototropic shift and allylic sulphoxide-sulphenate rearrangement (baseinduced, weak nucleophile) ;s and (c) the additive Pummerer (strong nucleophile) .9 These are additions to the numerous known vinyl sulplioxide reactions, and may also have wider synthetic applicability. RESULTS AND DISCUSSIONThe precursors, a-phenylthioacrylates, of compounds (1) were readily available from the reaction of the acarbanion species of (pheny1thio)acetic acid or its ester with ketones, followed by dehydration.1° Among a number of derivatives (1), methyl a-(phenylsulphiny1)-cyclopentylidene acetate (2) was chosen as a typical clerivative and exainined in detail.(a) Viwylogozrs Punamerer Rearrangement .-We examined first the reaction of compound (2) with acidic reagents (Scheme 2), and found that compound (2) underwent, on treatment with hot dilute sulphuric acid-dioxan or acetic anhydride, a novel rearrangement to produce y-ox ygen-f unct ionalised products. Thus, reaction of (2) with dilute sulphuric acid-dioxan for 3 h at reflux gave the 3-(yheny1thio)furanone (3) (53%) and the hydroxy-ester (4) (trace). The reaction of (2) with acetic. anhydride at 75 "C fo...
Enantiomer differentiation has been observed in the initial 1,5-phenyl shift of the sensitized photorearrangement of racemic 3-methyl-3-phenyl-2(3H)-oxepinone with chiral N-(1-phenylethyl)naphthalenecarboxamides leading to optically active 4-methyl-7-exo-phenyl-2-oxabicyclo[4.1.0]hept-4-en-3-one.
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