Abstract: A process for the preparation of an aromatic acid comprising the step of combining an aromatic halide having at least one iodine or bromine substituent with:a. a water-immiscible organic solvent,b. a palladium-based catalyst,c. a palladium-complexing agent,d. a tertiary nitrogen-containing organic base,e. water andf. carbon monoxide.The process is performed in a two-phase liquid medium and in the substantial absence of a phase transfer agent.

Abstract: Aromatic aldehydes are more efficiently produced by reacting carbon monoxide/hydrogen admixture with an aromatic halide in the presence of a noble metal-based catalyst, a tertiary nitrogenous based and, if necessary, a noble metal complexing agent, e.g., a phosphine or phosphite, wherein the CO/H.sub.2 ratio is less than 1.

Abstract: Aromatic aldehydes are more rapidly produced by reacting hydrogen/carbon monoxide admixture with an aromatic halide in the presence of a noble metal-based catalyst, a tertiary nitrogenous base and, if necessary, a noble metal complexing agent, e.g., a phosphine or phosphite, wherein the concentration of said tertiary nitrogenous base, expressed in moles per liter of reaction mixture, is maintained at a value of at least two moles/liter over the course of the reaction.

Abstract: .alpha.,.delta.-Diethylenic carbonyl compounds of the formula ##STR1## are made by an oxy-Cope rearrangement of an acetylenic alcohol of the formula ##STR2## in the presence of a catalyst based on a metal of Group Ib of the periodic table or palladium. In the formulae (I) and (II), R.sub.1, R.sub.2, R.sub.3 and R.sub.4, which may be identical or different, each denote a hydrogen atom or a hydrocarbon radical R.sub.2 and R.sub.3 being capable together of forming an alkylene radical (--CH.sub.2 --).sub.n in which one or more carbon atoms may be substituted by one or more alkyl radicals containing 1 to 4 carbon atoms, n is 3 to 20 inclusively and R.sub.5 denotes a hydrogen atom.

Abstract: Process for the preparation of .delta.-ethylenic carbonyl compounds of the formula: ##STR1## by the oxy-Cope rearrangement of a diethylenic alcohol of the formula: ##STR2## in which the transformation is carried out in the presence of a catalytic amount of a divalent palladium compound.In the depicted formulae R.sub.1, R.sub.4 and R.sub.6 each represent a hydrogen atom or a hydrocarbon radical, R.sub.2 represents a hydrogen atom and R.sub.3 and R.sub.5 each represent a hydrocarbon radical, or R.sub.3 and R.sub.4 together represent an alkylene radical (--CH.sub.2 --).sub.n (wherein n is an integer from 3 to 20 inclusive) in which one or more carbon atoms can optionally carry as substituent(s) one or more alkyl radicals containing 1 to 4 carbon atoms.The carbonyl products are useful as starting materials for the preparation of compounds intended for use in pharmacy, in agriculture or perfumery.

Abstract: Process for the preparation of .delta.-ethylenic carbonyl compounds of the formula (I) by the oxy-Cope rearrangement of a diethylenic alcohol of the formula (II), in the presence of a mercuric salt: in formulae (I) and (II), R.sub.1, R.sub.2, R.sub.4, R.sub.5 and R.sub.6, which are identical or different, represent a hydrogen atom or an acyclic hydrocarbon radical and R.sub.3 represents an acyclic hydrocarbon radical, it being understood that R.sub.1 and R.sub.3 can together form a trimethylene radical, or alternatively that R.sub.3 and R.sub.4 can together form an alkylene radical containing 3 to 20 carbon atoms.