Non‐Glovebox Ethenolysis of Ethyl Oleate and FAME at Larger Scale Utilizing a Cyclic (Alkyl)(Amino)Carbene Ruthenium Catalyst

• Published in: European journal of lipid science and technology Vol. 122; no. 1
• Main Authors: Kajetanowicz, Anna, Chwalba, Michał, Gawin, Anna, Tracz, Andrzej, Grela, Karol
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 01.01.2020
• Subjects: biomass; carbenes; Catalysts; cyclic (alkyl)(amino)carbene (CAAC) ligands; Decomposition reactions; Distillation; Esters; ethenolysis; Ethylene; Fatty acid methyl esters; fatty acid methyl esters (FAME); Fatty acids; Fine chemicals; Fractional distillation; Glove boxes; Metathesis; Oils & fats; olefin metathesis; oleic acid; Organic chemistry; Ruthenium; Selectivity; Substrates
• ISSN: 1438-7697; 1438-9312
• DOI: 10.1002/ejlt.201900263

A ruthenium metathesis catalyst Ru1 bearing a cyclic (alkyl)(amino)carbene (CAAC) ligand is used in the ethenolysis reaction of biosourced 90% pure undistilled ethyl oleate or technical fatty acid methyl esters mixture with grade 3 ethylene, to yield 1‐decene and valuable terminal unsaturated 9‐decenoic acid ester. Under optimized conditions (25 ppm of catalyst Ru1, 20 bar, 50 °C, 2 h, use of metal scavenger/quenching agent, SnatchCat), the title reaction proceeds with high productivity (up to 70% conversion) and selectivity, and is tested in scale up to 1 L, with the exclusion of a glovebox or Schlenk techniques usage, and the ethenolysis products are isolated by fractional distillation. In addition, a large‐scale synthesis of Ru1 is presented. Practical Applications: Decreasing availability of fossil organic feedstock and current policies of the European Union drives scientists to look for alternative sustainable sources of fine chemicals. In this context, olefin metathesis based ethenolysis of transesterified seed oils studied herein shows a significant potential as a sustainable way to obtain valuable products, such as 1‐decene and valuable terminal unsaturated 9‐decenoic acid ester. Unlike other published studies on ethenolysis, in the present work, the focus is on optimizing this reaction under industrially practical conditions, thus utilizing an air‐stable catalyst, technical grade oleic substrates, grade 3 ethylene, and excluding the use of a glovebox or Schlenk techniques. Ruthenium complex bearing a cyclic (alkyl)(amino)carbene ligand as a catalyst of choice for the ethenolysis of undistilled ethyl oleate or technical grade fatty acid methyl esters.