According to the present invention there is provided a compound in the form of a transition metal compound including a transition metal, a phosphorus containing ligand, and a cyclic organic ligand. The phosphorus containing ligand is a heterocyclic organic compound with a ligating phosphorus atom which ligates with the transition metal, and which ligating phosphorus atom is an atom in the heterocyclic ring structure of the heterocyclic organic compound. The cyclic organic ligand is a cyclic organic compound with a ligating carbon atom in the cyclic ring structure of the cyclic organic compound which ligates with the transition metal by means of a double bound. The invention also relates to a method preparing such a compound and a metathesis reaction wherein such a compound is used as a catalyst.