Abstract: Certain 1,4-cyclohexanediones are useful as antioxidants in photographic developing compositions. These compounds stabilize the compositions, are water soluble and are essentially odorless. These antioxidants can be used in either black and white or color developing compositions used to process photographic silver halide materials.

Abstract: Hydroxy-substituted hydroxylamine antioxidants can be prepared by reacting hydroxylamine or a mono-substituted hydroxylamine, in free base form, with an epoxide. The antioxidant reaction product can be used without isolation from the reaction solution, and combined with a color developing agent to provide a photographic color developing composition in either concentrated or working strength formulations. The method for preparing the antioxidant is rapid and efficient because of the use of the free base form of the hydroxylamine reactant, higher temperatures (at or above 50.degree. C.) and certain molar ratios of reactants.

Abstract: Disclosed is a process for the recovery of catalyst values from mixtures of catalyst compounds and oligomeric materials. The process provides for the separation of (i) an onium iodide compound, (ii) an organotin iodide compound, or (iii) a mixture thereof from a mixture thereof in an oligomer of a .gamma.,.delta.-epoxy-alkene by the steps of (1) intimately contacting the mixture with an extraction solvent selected from hydrocarbons having about 5 to 12 carbon atoms; (2) allowing the mixture of step (1) to separate into 2 phases; and (3) recovering the extraction solvent phase containing iodide compounds (i) and (ii). The oligomer mixture of compounds (i) and/or (ii) is formed during the manufacture of 2,5-dihydrofurans by the isomerization of .gamma.,.delta.-epoxyalkenes.

Abstract: Disclosed are processes for the isomerization of epoxyalkenes to dihydrofurans by contacting an epoxyalkene with a catalyst comprising a quaternary organic onium iodide compounds, optionally deposited on a non-acidic support and/or in combination with a Lewis acid co-catalyst. The catalyst may comprise a supported catalyst, an unsupported catalyst or a solution of the catalytically-active components in an inert, organic solvent.