Abstract: The present application provides compound of Formula X wherein A is an optionally substituted aliphatic or an optionally substituted aryl, and B is a moiety that stabilizes the partial positive charge at the carbon adjacent the divalent sulfur. The compound of Formula X is useful as a reversible antioxidant in a variety of applications. Also provided are methods of synthesizing the compound of Formula X.

Abstract: A solvent that reversibly converts from a nonionic liquid mixture to an ionic liquid upon contact with a selected trigger, e.g., contact with CO2, is described. In preferred embodiments, the ionic solvent is readily converted back to the nonionic liquid mixture. The nonionic liquid mixture includes an amidine or guanidine or both, and water, alcohol, or a combination thereof. Single component amine solvents that reversibly convert between ionic and non-ionic states are also described. Some embodiments require increased pressure to convert; others convert at 1 atmosphere.

Abstract: A solvent that reversibly converts from a nonionic liquid mixture to an ionic liquid upon contact with a selected trigger, e.g., contact with CO2, is described. In preferred embodiments, the ionic solvent is readily converted back to the nonionic liquid mixture. The nonionic liquid mixture includes an amidine or guanidine or both, and water, alcohol, or a combination thereof. Single component amine solvents that reversibly convert between ionic and non-ionic states are also described. Some embodiments require increased pressure to convert; others convert at 1 atmosphere.

Abstract: Methods of enhancing the solubility of a fluorinated compound in an organic solvent are provided. In one embodiment, carbon dioxide gas pressure is applied to the solvent at a pressure effective to enhance the solubility of the fluorinated compound. The method may further include recrystallizing the fluorinated compound by reducing the pressure of the carbon dioxide gas. Also provided are methods of conducting a reaction using a fluorinated compound in an organic solvent In one embodiment, the method comprises applying carbon dioxide pressure to an organic solvent comprising at least one substrate and a fluorinated catalyst, in an effective amount to solubilize the catalyst; and permitting the fluorinated catalyst to catalyze the reaction of the substrate to form a product. The catalyst is optionally separated from the reaction product and solvent after the reaction by the release of the pressure.