Improved systems and methods for producing propylene from olefins including isobutylene is disclosed. The improvements combine streams containing co-produced 1-butene, 2-butene, butadiene, and heavy olefins (C5+) exiting both a metathesis reactor and a skeletal isomerization reactor in a gasoline fractionation tower to remove the heavy olefins. The C4-containing distillate from the gasoline fractionation tower is then fed to a hydroisomerization unit to form mono-olefins and 2-butene. The resulting 2-butene rich stream can then be utilized in metathesis reactions to increase the production of propylene while increasing the lifetime of the metathesis catalyst.

The invention provides a new process for producing ruthenium complexes represented by the Formula 1. Invention provides also the use of ruthenium complexes represented by the Formula 1 as precatalysts and/or catalysts in olefin metathesis reactions.

The invention provides a new process for producing ruthenium complexes represented by the Formula 1. Invention provides also the use of ruthenium complexes represented by the Formula 1 as precatalysts and/or catalysts in olefin metathesis reactions.

One or more embodiments presently disclosed is directed to a method for reacting a chemical stream which may include contacting the chemical stream with a catalyst to produce a product stream. The catalyst may include alumina, silica, and a catalytically active compound such as tungsten.

One or more embodiments presently disclosed is directed to a method for reacting a chemical stream which may include contacting the chemical stream with a catalyst to produce a product stream. The catalyst may include alumina, silica, and a catalytically active compound such as tungsten.

Method of forming a trisubstituted ethylene compound, the method comprising: (A) providing a trisubstituted ethylene compound bearing a first, a second and a third substituent, in which the first and the second substituent are bound to the one olefinic carbon atom and are different from one another; (B) providing a monosubstituted ethylene compound or a disubstituted ethylene compound in which the substituents are vicinally bound to the olefinic carbon atoms, bearing at least a fourth substituent, respectively; (C) subjecting the trisubstituted ethylene compound provided in step (A) to a cross-metathesis reaction with olefin provided in step (B) to form said trisubstituted ethylene, wherein the cross-metathesis reaction is catalysed by a transition metal complex bearing ligands from which one ligand is a carbene ligand, wherein the carbene complex is characterized by a M=C moiety, wherein M is the transition metal; and wherein the reaction proceeds stereoselectively.

Method of forming a trisubstituted ethylene compound, the method comprising: (A) providing a trisubstituted ethylene compound bearing a first, a second and a third substituent, in which the first and the second substituent are bound to the one olefinic carbon atom and are different from one another; (B) providing a monosubstituted ethylene compound or a disubstituted ethylene compound in which the substituents are vicinally bound to the olefinic carbon atoms, bearing at least a fourth substituent, respectively; (C) subjecting the trisubstituted ethylene compound provided in step (A) to a cross-metathesis reaction with olefin provided in step (B) to form said trisubstituted ethylene, wherein the cross-metathesis reaction is catalysed by a transition metal complex bearing ligands from which one ligand is a carbene ligand, wherein the carbene complex is characterized by a M=C moiety, wherein M is the transition metal; and wherein the reaction proceeds stereoselectively.

Embodiments in accordance with the present invention encompass an organoruthenium compound of the formula (I) or formula (II):

##STR00001##

Wherein X, L, R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, Ar.sub.1 and Ar.sub.2 are as defined herein. Also disclosed herein are the use of organoruthenium compound of formula (I) or formula (II) as (pre)catalysts for the olefin metathesis reactions, as well as to the process for carrying out the olefin metathesis reaction.

Embodiments in accordance with the present invention encompass an organoruthenium compound of the formula (I) or formula (II): ##STR00001##
Wherein X, L, R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, Ar.sub.1 and Ar.sub.2 are as defined herein. Also disclosed herein are the use of organoruthenium compound of the formula (I) or formula (II) as (pre)catalysts for the olefin metathesis reactions, as well as to the process for carrying out the olefin metathesis reaction.

Embodiments in accordance with the present invention encompass an organoruthenium compound of the formula (I) or formula (II): ##STR00001##
Wherein X, L, R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, Ar.sub.1 and Ar.sub.2 are as defined herein. Also disclosed herein are the use of organoruthenium compound of the formula (I) or formula (II) as (pre)catalysts for the olefin metathesis reactions, as well as to the process for carrying out the olefin metathesis reaction.