The ruthenium-catalyzed cross-metathesis of eugenol derivatives with electron deficient olefins is reported. It is shown that in the presence of ruthenium catalysts, eugenol and its O-protected derivatives have a high tendency to undergo carbon–carbon double bond migration before and after metathesis leading to the formation of conjugated styrene derivatives. The addition of 1,4-benzoquinone suppresses these isomerization reactions and provides an efficient access to new polyfunctional phenol derivatives upon cross-metathesis of the biosourced eugenol with acrylates, acrylonitrile and acrylamides.