Oleic acid (OA) is a renewable monounsaturated fatty acid obtained from high oleic sunflower oil. This work was focused on the oxidative scission of OA, which yields a mono‐acid (pelargonic acid, PA) and a di‐acid (azelaic acid, AA) through an emulsifying system. The conventional method for producing AA and PA consists of the ozonolysis of oleic acid, a process which presents numerous drawbacks. Therefore, we proposed to study a new alternative process using a green oxidant and a solvent‐free system. OA was oxidized in a batch reactor with a biphasic organic‐aqueous system consisting of hydrogen peroxide (H2O2, 30 %) as an oxidant and a peroxo–tungsten complex Q3{PO4[WO(O2)2]4} as a phase‐transfer catalyst/co‐oxidant. Several phase‐transfer catalysts were prepared in situ from tungstophosphoric acid, H2O2 and different quaternary ammonium salts (Q+, Cl–). The catalyst [C5H5N(n‐C16H33)]3{PO4[WO(O2)2]4} was found to give the best results and was chosen for the optimization of the other parameters of the process. This optimization led to a complete conversion of OA into AA and PA with high yields (>80 %) using the system OA/H2O2/[C5H5N(n‐C16H33)]3{PO4[WO(O2)2]4} (1/5/0.02 molar ratio) at 85 °C for 5 h. In addition, a new treatment was developed in order to recover the catalyst.

-In a context of dwindling oil reserves and environmental pressures, the chemical industry needs to innovate by developing new processes for producing bioproducts from raw plant materials. Unsaturated fatty acids from vegetable oils constitute a highly promising renewable resource that can be used to diversify productions, decreasing reliance on petroleum. A starting material rich in oleic acid has been obtained through the selection of high-oleic sunflower varieties and enzymatic hydrolysis of the oil they produce. The double bonds of this unsaturated raw material have been cleaved in green oxidizing conditions involving a biphasic lipophilic-aqueous system including hydrogen peroxide as an oxidant and a peroxo-tungsten complex Q 3 {PO 2 [WO(O 2 ) 2 ] 4 } as a phase-transfer catalyst (PTC) and co-oxidant. This PTC efficiently transferred oxygen to the substrate in the lipophilic phase. A mono-acid (pelargonic acid) and a di-acid (azelaic acid), with shorter, unusual hydrocarbon chains not present in the natural state, were synthesized and purified through an intensive process. Pelargonic acid was then formulated as an environmentally friendly biocontrol agent for weeds. We extended this green process of oxidative scission to other fatty acids and derivatives, to obtain other short-chain acids with diverse potential applications. This production chain (crops, reaction and purification processes, products, applications) is based on a sustainable development strategy. Keywords:Oxidative scission / oleic acid / green process / ecodesign / biocontrol Résumé -De la plante aux bioproduits destinés au biocontrôle : préserver l'écosystème par l'utilisation de molécules biosourcées. Dans un contexte de diminution des réserves fossiles et de pressions réglementaires et environnementales, l'industrie chimique tend à innover en développant de nouveaux procédés pour la production de bioproduits d'origine végétale. Les acides gras insaturés d'une huile végétale constitue une ressource renouvelable prometteuse qui peut être utilisée pour diversifier les productions et réduire la dépendance vis-à-vis du pétrole. Dans cet article, une matière première riche en acide oléique a été obtenue par l'hydrolyse enzymatique de l'huile de tournesol hautement oléique, obtenue par sélection variétale. Les doubles liaisons de cette matière première insaturée ont été clivées dans des conditions oxydantes impliquant un système biphasique aqueux-lipophile, avec le peroxyde d'hydrogène comme oxydant et le complexe peroxo-tungtène Q 3 {PO 2 [WO(O 2 ) 2 ] 4 } comme catalyseur de transfert de phase (CTP) et cooxydant. Ce CTP a permis d'assurer un transfert efficace vers le substrat en phase lipophile. Un mono-acide (acide pélargonique) et un di-acide (acide azélaïque) à chaînes impaires plus courtes, peu présentes à l'état naturel, ont été ainsi synthétisés et purifiés grâce à un procédé intensifié. L'acide pélargonique a été formulé en tant qu'agent de biocontrôle écocompatible. Ce procédé vert de scission oxydante a été appliqué à d'autr...

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