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.