RESUMEN
The transformation of cooking oils and their waste into polyesters is a challenge for circular chemistry. Herein, we have used epoxidized olive oil (EOO), obtained from cooking olive oil (COO), and various cyclic anhydrides (such as phthalic anhydride PA, maleic anhydride MA, and succinic anhydride SA) as raw materials for the preparation of new bio-based polyesters. For the synthesis of these materials, we have used the bis(guanidine) organocatalyst 1 and tetrabutylammonium iodide (Bu4NI) as cocatalyst. The optimal reaction conditions for the preparation of poly(EOO-co-PA) and poly(EOO-co-MA) were 80 °C for 5 h using toluene as solvent; however, the synthesis of poly(EOO-co-SA) required more extreme reaction conditions. Furthermore, we have exclusively succeeded in obtaining the trans isomer for MA-polyester. The obtained biopolyesters were characterized by NMR, Fourier transform infrared, thermogravimetric analysis, and scanning electron microscopy analyses. Since there are few examples of functionalized and defined compounds based on olive oil, it is innovative and challenging to transform these natural-based compounds into products with high added value.
RESUMEN
The molecular structures of (E)-1-(4-{[1-(4-fluorophenyl)-3,5-dimethyl-1H-pyrazol-4-yl]diazenyl}phenyl)ethanone, C19H17FN4O, (III), and (E)-1-(4-chlorophenyl)-3,5-dimethyl-4-[2-(2-nitrophenyl)diazenyl]-1H-pyrazole, C17H14ClN5O2, (IV), prepared by reaction of the corresponding ß-diketohydrazones with substituted arylhydrazines in acid media, are nonplanar, with the planes of the lateral phenyl rings forming dihedral angles with that of the central pyrazole ring varying from 2.71â (7) to 45.22â (7)°. The crystal structures are supported by C-H...O, C-H...π and π-π weak intermolecular interactions together with some unusual trifurcated C-Cl...Cl-C contacts, which are discussed in detail.
