Patent ID: 8722953

Claim:
A process for preparing a substituted or unsubstituted 1,7-diolefin, comprising: hydrodimerizing a non-cyclic olefin having at least two conjugated double bonds in a presence of a reducing agent and a catalyst, wherein the reducing agent comprises at least one selected from the group consisting of formic acid and a formate, the reducing agent is metered in during a course of the hydrodimerizing of the non-cyclic olefin such that a ratio of the non-cyclic olefin to the reducing agent is from 1:1 to 10:1, and the catalyst comprises a metal-carbene complex which has a metal of group 8 to 10 of the Periodic Table and at least one carbene ligand of the structure 2 where: R 1 , R 2 =—(CH 2 ) n —B B=mono- or polycyclic aryl group having 6 to 14 carbon atoms or mono- or polycyclic heterocycle having 5 to 14 carbon atoms and heteroatoms, where this heterocycle has 1 to 3 heteroatoms selected from the group consisting of N, O and S, n=0-4 and R 3 and R 4 =substituents selected from the group consisting of hydrogen, alkyl, heteroaryl, aryl, —CN, —COOH, —COO-alkyl, —COO-aryl, —OCO-alkyl, OCO-aryl, —OCOO-alkyl, OCOO-aryl, —CHO, —CO-alkyl, —CO-aryl, —NH 2 , —NH(alkyl), —N(alkyl) 2 , NH(aryl), —N(aryl) 2 , —F, —Cl, —Br, —I, —OH, —CF 3 , —NO 2 , -ferrocenyl, —SO 3 H, and —PO 3 H 2 , where the alkyl groups have 1 to 12 carbon atoms and the aryl groups 5 to 14 carbon atoms, and the substituents of R 3 and R 4 may also be part of a bridging aliphatic or aromatic ring, and the substituents of R 1 and R 2 are the same or different and are substituted or unsubstituted, and the substituents of R 3 and R 4 are the same or different and are substituted or unsubstituted.