AUTHOR=Lanteri Deianira , Quattrosoldi Silvia , Soccio Michelina , Basso Andrea , Cavallo Dario , Munari Andrea , Riva Renata , Lotti Nadia , Moni Lisa 

TITLE=Regioselective Photooxidation of Citronellol: A Way to Monomers for Functionalized Bio-Polyesters

JOURNAL=Frontiers in Chemistry

VOLUME=8

YEAR=2020

URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2020.00085

DOI=10.3389/fchem.2020.00085

ISSN=2296-2646

ABSTRACT=<p>Dye-sensitized photooxygenation reaction of bio-based double bond-containing substrates is proposed as sustainable functionalization of terpenes and terpenoids to transform them into polyoxygenated compounds to be employed for the synthesis of new bio-based polyesters. As proof of concept, citronellol <bold>1</bold> has been regioselectively converted into diol <bold>4</bold> using singlet oxygen (<sup>1</sup>O<sub>2</sub>), a traceless reagent that can be generated from air, visible light and zeolite supported-photosensitizer (Thionine-NaY). With our synthetic approach, diol <bold>4</bold> has been obtained in two-steps, with good regioselectivity, using green reagents such as light and air, and finally a solvent-free oxidation step. From this compound, a citronellol-based copolyester of poly(butylene succinate) (PBS) has been synthesized and fully characterized. The results obtained evidence that the proposed copolymerization of PBS with the citronellol-based building blocks allows to obtain a more flexible and functionalizable material, by exploiting a largely available natural molecule modified through a green synthetic path.</p>