Abstract: The alkyl hydroquinones, e.g., methyl hydroquinone (a useful intermediate in the preparation of the monomer methyl hydroquinone diacetate, itself used for the synthesis of thermotropic polymers), are prepared by reacting (C-alkylating) hydroquinone or a monoether thereof with a lower alkanal, in the vapor phase, with a catalytically effective amount of at least one solid metal oxide.

Abstract: The invention relates to chemical compounds and their use as catalysts in the solvolysis of alkyl halides. The chemical compounds, when dry, have formula (I):(EO.sub.4 M).multidot.(Imp)p (I)wherein E is selected from the group consisting of phosphorus, arsenic, antimony and bismuth, and is preferably phosphorus, and M is a metal or a mixture of metals.Imp corresponds to a basic impregnating compound consisting of alkaline earth metal, or preferably alkali metal, and their mixtures in combination with a counter-anion to ensure electrical neutrality.The coefficient p is between 10.sup.-2 and 1/3.

Abstract: Dinitrotoluenes are prepared by reacting mononitrotoluene(s) with nitric acid, in liquid phase, in the presence of an inorganic and acidic solid including at least one component selected from among orthophosphoric acid, pyrophosphoric acid, metaphosphoric acid, a metal dihydrogen phosphate, a metal hydrogen phosphate, a metal orthophosphate or a metal pyrophosphate, such metal cations having from 1 to 5 positive charges.

Abstract: A process for the preparation of trifluoroethanol by hydrolysis, in the gas phase, of chlorotrifluoroethane. A gaseous mixture of 1-chloro-2,2,2-trifluoroethane and water is contacted with a solid catalyst and taken to a temperature greater than 350.degree. C. and preferably between 400.degree. and 500.degree. C. 2,2,2-Trifluoroethanol (TFE) is a trifluorinated alcohol possessing very good thermal stability, which makes it suitable for a certain number of applications, in particular in the synthesis of fluorinated anesthetics, in pharmacology in general, and as a solvent.

Abstract: Methyl acetate is carbonylated, advantageously to acetic anhydride, in a homogeneous liquid phase, advantageously in a virtually anhydrous reaction medium, in the presence of (a) a cobalt source, (b) a source of iron in the zero oxidation state, (c) an ionic iodide of the formula A.sup.+ I.sup.- in which A.sup.+ is a nitrogen group quaternary onium cation, or an alkali metal cation, and, (d) if appropriate, a carboxylate of the formula A'.sup.n+ (OCOR).sub.n.sup.-, in which n is 1 or 2 and A'.sup.n+ is defined as was A.sup.+, or is an alkaline earth metal cation, with A'.sup.n+ and A.sup.+ either being the same or different, and R is an alkyl, aralkyl or aryl radical having a maximum of 8 carbon atoms, with the total amount of halogen compounds present in the carbonylation reaction medium (expressed in gram atoms of halogen and designated by X.sub.T) being such that the atomic ratio X.sub.T /(A.sup.+ +n.A'.sup.n+) is less than or equal to 1.