Process for metathesis of olefins obtained from fischer-tropsch fractions using a ruthenium complex comprising a symmetric n-heterocyclic diaminocarbene

Process for metathesis of olefins from feedstocks obtained from the Fischer-Tropsch process, using as catalyst a ruthenium indenylidene complex of Formula (I) or (II)

• in which:
• R1 is a linear or branched alkyl group, a monocyclic or polycyclic cycloalkyl group, an aromatic monocyclic or bicyclic aryl group, or a linear or branched arylalkyl group that carries an aromatic cycle,
• a, b, c, d, e, and f are selected independently from one another in the group that consists of a hydrogen atom, an alkyl group, and a heteroalkyl group,
• X1 and X2, identical or different, are anionic ligands,
• L is a ligand that is an electron donor and uncharged,
• R2, R3, R4, R5—identical or different—are hydrogen, halide, alkyl, cycloalkyl, aryl or arylalkyl groups, each being able to be substituted by alkyl, halide, or alkoxy groups or by a phenyl group that is optionally substituted by halide, alkyl, or alkoxy groups.