The Multiple Faces of Eugenol. A Versatile Starting Material and Building Block for Organic and Bio-Organic Synthesis and a Convenient Precursor Toward Bio-Based Fine Chemicals

Phenylpropenes are produced by plants as part of their defense strategy against microorganisms and animals, and also as floral attractants of pollinators. Eugenol, the main component of clove’s essential oil, is an inexpensive and easily available phenylpropene that has been known by humankind since antiquity, and used as a medicinal agent, but also for food flavoring and preservation. The review includes the most relevant results obtained during the last 15 years with regard to the synthetic uses of eugenol. Discussed here are the multiple applications of eugenol in organic synthesis, including its use as starting material or building block for the total synthesis of natural products, their analogs and derivatives, as well as other structurally interesting or bioactive compounds. The preparation technologically relevant macrocycles and polymeric derivatives of eugenol, is included, and the impact of biotechnology on the use of eugenol as feedstock for biotransformations, leading to other valuable small molecules is also addressed.