In this paper, the piperine (PIP) and eugenol (EUG) organic compounds were used as substrates in olefin metathesis reactions catalyzed by first-generation Grubbs catalyst (G1) - [RuCl2(PCy3)2(=CHPh)], Cy is cyclohexyl and Ph is phenyl, in a one-pot system. The reactions occurred at 50 ºC, for 24, 48, or 96 h using the two substrates simultaneously in the ratio Ru:PIP:EUG of 1:1:1 and 1:10:10 mol. The results were evaluated by GC-MS, discussed in terms of the electronic and steric characteristics of the G1, and the structural proprieties of the substrates. In the Ru:PIP:EUG ratio of 1:1:1 mol, a dimeric species was observed for the olefin metathesis of EUG, in all time studied and in an additional experiment at 70 ºC for 48 h. When the Ru:PIP:EUG ratio was 1:10:10 mol, this dimer was not observed. Isomerization processes also were observed at all temperatures and catalyst:substrates ratio. The reaction yield increased with the raise of substrates amount. There was no cross-metathesis reaction. This fact was attributed to the chelating effect of the double coordination of the PIP to the catalyst.

LN-1 and LN-2 are two Ru(II) complexes coordinated to the phosphine and amines simultaneously, each with two chlorides. PPh3 is the phosphine and the amine is piperidine (LN-1) and perhydroazepine (LN-2). The two compounds are complexes five-coordinated square pyramidal geometry, with the amine in the axial plane. LN-1 and LN-2 were tested for the first time as initiator for piperine self-metathesis olefin. The system variables chosen to this study were the reactional time (24, 48 and 72 h), catalyst:substrate ratio (1:1 and 1:10 mol) and temperature (25 e 50 ºC). Results were analyzed by GC-ME. None olefin metathesis product was noted in the experiments to 25 ºC for until 72 h, in any catalyst:substrate ration. However, to 50 ºC for 72 h, olefin metathesis product from piperine was observed. LN-1 presented yield of c.a. 29% of product in the mixture and LN-2 were c.a. 39%. The product is interesting and unheard, it has two 1,3-benzildiaxine groups, interleaved for one unsaturated carbon chain. In the experiments with catalyst:substrate ratio of 1:10 mol there was no product formation. The results were discussed in function of the electronic and steric properties of the ancillary ligand of LN1 and LN-2.