Abstract: A process for the preparation of organic compounds or polymers containing one or more sulphur atoms and including one or more double bonds in a hydrocarbon chain is described. An acyclic sulphur-containing olefin or an unsaturated sulphur-containing cyclic hydrocarbon undergoes a self metathesis reaction or a cross metathesis reaction with a non-sulphur-containing acyclic olefin or a non-sulphur-containing unsaturated cyclic hydrocarbon to produce novel olefins, novel dienes, and/or olefinic polymers containing one or more sulphur atoms.

Abstract: Process of polymerization of unsaturated hydrocarbons, with an initial induction period, by means of a catalyst constituted by a halogeno-phenate of tungsten, of which the phenate group carries one or more substituents, in the presence of an organometallic co-catalyst; the halogeno-phenate is chosen from amongst those represented by the formula ##STR1## where X is a halogen, especially Cl or Br, n is a whole number 2, 3 or 4, R.sup.1 is H or a C.sub.1 to C.sub.8 straight- or branched-chain alkoxy group, R.sup.2 is H or a C.sub.3 to C.sub.9 branched-chain alkyl group, R.sup.1 and R.sup.2 never being hydrogen simultaneously.

Abstract: Improved catalytic systems of long active duration, comprising initially (a) a tungsten compound, (b) an organometallic compound and (c) a partially or totally fluorinated organic compound.Process of stabilization of these catalytic systems, comprising dissolving (a) in an organic solvent, contacting (b) with (a), agitation and heating at 0.degree. to 100.degree. C. for 0.5 to 60 minutes, then introduction of (c) into the mixture of (a) and (b).Use of these stabilised catalytic systems for the metathesis of olefins which carry functional groups or do not carry such groups.

Abstract: Improved process of metathesis of olefins by contact of one or more olefins with a catalyst comprising a tungsten complex with two phenoxy groups, carrying substituents and four other ligands, the complex carrying as coordination groups a halogen atom, an alkyl radical and a carbene. The catalyst preferably is of the formula ##STR1## where X is halogen, R is hydrocarbon or an electronegative group or atom, R.sup.1 is alkyl and R.sup.2 and R.sup.3 are individually hydrogen or alkyl groups.

Abstract: Improved catalyst for the metathesis of olefins comprising a compound of W with a halogen and with a phenoxy group which can carry substituents. It contains 4 halogen atoms and 2 phenoxy groups per atom of W. Preferably, the phenoxy group is halogenated. This catalyst allows the more rapid carrying out of various types of metathesis reactions, when it is used as a co-catalyst in conjunction with organo-metallic compounds, particularly Al or Sn. Amongst others, it allows the economical preparation of pheromones. It is practically insensitive to traces of water and oxygen.

Abstract: Improved catalyst for the metathesis of olefins comprising a compound of W with a halogen and with a phenoxy group which can carry substituents. It contains 4 halogen atoms and 2 phenoxy groups per atom of W. Preferably, the phenoxy group is halogenated. This catalyst allows the more rapid carrying out of various types of metathesis reactions, when it is used as a co-catalyst in conjunction with organo-metallic compounds, particularly Al or Sn. Among others, it allows the economical preparation of pheromones. It is practically insensitive to traces of water and oxygen.