Supporting Information

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1 Supporting Information Synthesis of 1,6-Hexandiol, Polyurethane Monomer Derivatives via Isomerization Metathesis of Methyl Linolenate Ervin Kovács, a Gábor Turczel, a Lili Szabó, a Réka Varga, a Imre Tóth, a Paul T. Anastas b * and Róbert Tuba a * a Institute of Materials and Environmental Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, 1519 Budapest, P.O. Box 286, Hungary. b Center for Green Chemistry and Engineering, Yale University, New Haven, Connecticut 06511, USA * robert.tuba@ttk.mta.hu, paul.anastas@yale.edu Contents 1. General information Cross metathesis of ESA methyl ester (1) and cis-1,4-diacetoxy-2-butene (2) Cross metathesis of tung oil and cis-1,4-diacetoxy-2-butene (2) Isomerisation reaction of linolenic acid methyl ester (8) Isomerisation of linolenic acid methyl ester (8) and cross metathesis of the reaction mixture with cis-1,4-diacetoxy-2-butene (2) References... 7 This document contains three Figures and three Tables over seven pages. S1

2 1. General information All reactions were conducted under nitrogen atmospheres using Schlenk-technique or under argon using a glovebox. 3-G2, 3-HG2 (Materia), RuHCl(CO)(PPh 3 ) 3 (9) catalyst (Aldrich), palladium on carbon (Aldrich), cis-2-butene-1,4-diol, tung oil (Aldrich), α- linolenic acid (70 %), toluene-d 8, ethylbenzene and other solvents (Aldrich), were used as received. 3-G3 was synthetized according to literature procedure. 1 1 and 8 esters were also prepared according to standard literature procedures. 2,3 The overall yield has been determined for each reaction product using GC and 1 H NMR techniques. Routine 1 H NMR spectra were obtained on a Varian Unity INOVA spectrometer operating at an equivalent 1 H frequency of 500 MHz. GC-MS analyses were carried out using a Shimadzu GC-MS-QP2010 instrument equipped with a Rxi-5Sil MS column coupled with a quadrupole mass filter with pre-rods. S2

3 2. Cross metathesis of ESA methyl ester (1) and cis-1,4-diacetoxy-2-butene (2) A Schlenk tube was charged with 1 (0.101 g, mmol), 2 (0.658 ml, 4.12 mmol, 12 equiv.) and ethylbenzene (0.042 ml, mmol) as internal standard in a glovebox. A solution of the catalyst (3, mmol, 5 mol% of 1) in toluene (0.15 ml) was added. The Schlenk tube was either removed from the glovebox and fitted to a condenser, the mixture was heated at 100 C for 2 hours with stirring (Condition A) or simply stirred in the glovebox at room temperature for 24 hours (Condition B). Portion of the mixture was hydrogenated on atmospheric pressure using 10% Pd/C in ethanol overnight at room temperature. The black suspension was filtered and the filtrate was analyzed by GC-MS (Figure S1, Table S1). * Figure S1. Total ion current (TIC) chromatogram of the hydrogenated cross metathesis of α-eleostearic acid methyl ester (1) and cis-1,4-diacetoxy-2-butene (2) using 3-HG2 catalyst. *Hydrogenated excess of 2 Table S1. Composition of the hydrogenated reaction mixture of the cross metathesis of 1 and 2 using 3-HG2. T R (min) Area% Name Ethylbenzene a Heptyl acetate (7) ,6-Diacetoxyhexane (5) ,8-Diacetoxyoctane (5*) b Methyl 11-acetoxyundecanoate (4) Methyl 13-acetoxytridecanoate c Methyl stearate d a Internal standard, b Homologue of 5, c Homologue of 4, d Hydrogenated 2 S3

4 3. Cross metathesis of tung oil and cis-1,4-diacetoxy-2-butene (2) A Schlenk tube was charged with pre-treated 4 tung oil ( ml, 0.10 mmol), cis-1,4- diacetoxy-2-butene (2, ml, 3.86 mmol, three-fold excess per double bond of lipid) and ethylbenzene (0.038 ml, 0.31 mmol) as internal standard and fitted to a condenser. A solution of the catalyst (3-HG2, g, mmol, 5 mol% of eleostearic acid) in toluene (2.0 ml) was added. The mixture was heated at 100 C for 2 hours, cooled down to room temperature. A portion of the mixture was hydrogenated on atmospheric pressure using 10% Pd/C in ethanol for overnight at room temperature. The black suspension was filtered. The mixture was analyzed by GC-MS (Figure S2, Table S2) * Figure S2. Total ion current (TIC) chromatogram of the hydrogenated cross metathesis of tung oil and cis-1,4-diacetoxy-2-butene (2) using 3-HG2 catalyst. *Hydrogenated excess of 2 Table S2. Composition of the hydrogenated reaction mixture of the metathesis of tung oil and 2. T R (min) Area% Name Ethylbenzene a Hexyl acetate b Heptyl acetate (7) Nonyl acetate b Decyl acetate b ,6-Diacetoxyhexane (5) Undecyl acetate b Dodecyl acetate b ,8-Diacetoxyoctane (5*) c Tridecyl acetate b ,10-Diacetoxydecane c a Internal standard, b Homologue of 7, c Homologue of 5 S4

5 4. Isomerisation reaction of linolenic acid methyl ester (8) A screw cup NMR tube was charged with 8 (0.300 g, 1.03 mmol). Toluene-d 8 (0.75 ml) and catalyst 9 ( g, mmol, 0.5 mol% of 8) were added. The brownish mixture was heated at 90 C for 24 hours, collecting NMR spectra at t[min]= 0, 30, 60, 120, 160, 240, 1440 (Figure S3: 1440 min). The formed mixture was a clear yellow solution. Figure S3. 1 H NMR spectra of the reaction mixture after 24 hours of isomerisation of 8 in the presence of 9 in toluene-d 8. S5

6 5. Isomerisation of linolenic acid methyl ester (8) and cross metathesis of the reaction mixture with cis-1,4-diacetoxy-2-butene (2) A Schlenk tube was charged with 8 (0.253 g, mmol) and fitted to a condenser. Toluene (0.5 ml) and catalyst 9 (0.016 g, mmol, 2 mol% of 8) were added. The brownish mixture was heated at 100 C for 4 hours, cooled down to room temperature. Cis-1,4-diacetoxy-2-butene (2, 2.54 ml, 15.9 mmol, 18 equiv.), ethylbenzene (0.106 ml, mmol) as internal standard and Grubbs 2 nd generation catalyst (3-G2, g, mmol, 2 mol% of ester) were added. The brownish mixture was stirred overnight at room temperature. A portion of the mixture was hydrogenated at atmospheric pressure using 10% Pd/C in ethanol for overnight at room temperature. Then, the black suspension was filtered. The mixture was analyzed by GC-MS (Figure 2, Table S3). Table S3. Composition of the hydrogenated reaction mixture of the metathesis of isomerized 8 and 2. T R (min) Area% Name Ethylbenzene a Pentyl acetate (n = 2) Hexyl acetate (n = 3) Heptyl acetate (7, n = 4) Nonyl acetate (n = 6) Decyl acetate (n = 7) ,6-Diacetoxyhexane (5) Methyl 7-acetoxyheptanoate (m = 3) Undecyl acetate (n = 8) Methyl 8-acetoxyoctanoate (m = 4) Dodecyl acetate (n = 9) ,8-Diacetoxyoctane (5*) b Methyl 9-acetoxynonanoate (m = 5) Tridecyl acetate (n = 10) Methyl 10-acetoxydecanoate (m = 6) ,10-Diacetoxydecane b Methyl 11-acetoxyundecanoate (4, m = 7) Methyl 12-acetoxydodecanoate (m = 8) Methyl 13-acetoxytridecanoate (m = 9) Methyl 14-acetoxytetradecanoate (m = 10) a Internal standard, b Homologue of 5 S6

7 6. References (1) Love, J. A.; Morgan, J. P.; Trnka, T. M.; Grubbs, R. H. A practical and highly active ruthenium-based catalyst that effects the cross metathesis of acrylonitrile. Angew. Chemie - Int. Ed. 2002, 41 (21), , DOI: / ( )41 (2) Kovács, E.; Sághy, P.; Turczel, G.; Tóth, I.; Lendvay, G.; Domján, A.; Anastas, P. T.; Tuba, R. Metathesis of renewable polyene feedstocks Indirect evidences of the formation of catalytically active ruthenium allylidene species. J. Organomet. Chem. 2017, 847, , DOI: /j.jorganchem (3) Tormo, J. R.; Zafra-Polo, M. C.; Serrano, A.; Estornell, E.; Cortes, D. Epoxyacetogenins and other polyketide epoxy derivatives as inhibitors of the mitochondrial respiratory chain complex I. Planta Med. 2000, 66 (4), , DOI: /s (4) Öztürk, B. Ö.; Topoglu, B.; Karabulut Sehitoglu, S. Metathesis reactions of rapeseed oil-derived fatty acid methyl esters induced by monometallic and homobimetallic ruthenium complexes. Eur. J. Lipid Sci. Technol. 2015, 117 (2), , DOI: /ejlt S7