9-Octadecenedioic acid

This example illustrates the second stage (optional) of homometathesis of the 9-decenoic acid resulting from the first stage to give the diacid of formula COOH-(CHCompound 4 was prepared according to a literature procedure.2 Oleic acid (89 g (90percent), 0.315 mol)was transferred into a 250-mL three-necked round-bottomed flask via syringe and out gassed with N2 for 0.5 h. 1, 3-Bis-(2, 4, 6-trimethylphenyl)-2-(imidazolidinylidene) (dichlorophenylmethylene)-tricyclohexylphosphine) ruthenium (267 mg, 0.315 mmol), 2nd generation Grubbs catalyst, was then added. The reaction mixture was stirred with a mechanical stirrer and heated at 45°C, and after ~5min the diacid began to precipitate from the reaction mixture. After 3 days stirring the crude product was quenched with ethyl vinyl ether (40 mL), and excess ether was removed under reduced pressure. The residue was recrystallized several times from a mixture of hexane (300 mL) and ethylacetate (50 mL) to give pure 4 as a white solid (23.5 g, 7.52 mmol, 47 percent). m.p. 97–98 °C. 1H NMR(300 MHz, CD3OD): δ 5.39 (m, 2H, –CH=CH–), 2.27 (t, 4H, J = 7.35 and 7.35 Hz, –CH2–COOH), 1.97 (m, 4H), 1.60 (m, 4H), 1.32 (m, 16H, –CH2–). 13C NMR (75 MHz, CD3OD): δ181.0 (s, –COOH), 131.6 (d, 2C, –CH=CH–), 35.1, 33.7, 30.8, 30.4, 30.3, 30.2, 26.2.Oleic acid (76 g) was transferred into a 250 mL three-necked round bottom flask and stirred at 45° C. under nitrogen gas for 0.5 hours. Grubbs 2Oleic acid ((3b), 89 g (90percent, 0.315 mol) was transferred into a 250 mL 3-neck round bottom flask via syringe and out-gassed with nitrogen gas for 0.5 h. 1, 3-Bis-(2, 4, 6-trimethylphenyl)-2-(imidazolidinylidene)(dichlorophenylmethylene)(tricyclohexylphosphine)ruthenium (2, 267 mg, 0.315 mmol), a second generation Grubbs catalyst, was then added; no solvent was utilized. The reaction mixture was stirred with a mechanical stirrer and heated at 45° C. and after about 5 minutes a white precipitate formed. After 24 h reaction, about 10 mg of crude product was removed from the reaction mixture and transferred to a 2 mL dram vial. The crude diacid product (5b, eq. 1) was added to 1 mL of methanol and two drops of conc. sulfuric acid were added. The resulting mixture was heated at 80° C. for 0.5 h (Christie, W. W., Lipid analysis: Isolation, Separation, Identification, and Structural Analysis of Lipids, Oxford, N.Y. Pergamon Press (1982)). The reaction mixture was then quenched with 2 mL of 1M NaIn a typical experiment, 2.7 mg of G2 (3.2 μmol) was dissolved in 10 g of oleic (35.4 mmol) in a 100 ml glass flask under an NIn a typical experiment, 2.7 mg of G2 (3.2 μmol) was dissolved in 10 g of linoleic(35.7 mmol) in a 100 ml glass flask under an N2 atmosphere. The reaction mixture wasstirred and heated at 50C in an oil bath for 72 hours. The reaction mixture wasdissolved in small amount of CHCl3 and precipitated in hexane. The mixture was thenfiltrated and the resulting solid was washed with hexane to give a white powder:Octadec-9-enedioic acid in a 23percent yield.Similar to oleic acid above, ricinoleic acid (8, 400 mg 1.34 mmol) was mixed with 2 (11 mg, 0.013 mmol) in a 50 mL Schlenck tube under nitrogen gas flow and the mixture was heated at 50° C. After about 0.5 h, a small amount of white precipitate was observed in the reaction flask. After 3 days of stirring at 50° C., the reaction mixture was quenched with 2 mL of ethyl vinyl ether and the volatile components removed under reduced pressure. The crude product contains the diol 9, ricinoleic acid, and diacid 5b was methylated using the procedure described above. The methylated product (116 mg) was reacted with 400 μL of N, O-bis(trimethylsilyl)trifluoroacetamide and 120 μL of pyridine at room temperature for 1 h (Christie, W. W., Lipid analysis: Isolation, Separation, Identification, and Structural Analysis of Lipids, Oxford, N.Y. Pergamon Press (1982)). The silylated product was purified by passage through a silica gel column (about 20 g, I.D. X Length (0.5.x.10)) using hexane:ethyl acetate (9:1 v/v) as eluant to give 34.5 mg of 7, 12-bis(trimethylsiloxy)octadec-9-ene (9a) as yellow oil, 28.9 mg of the silylated methyl ester of 8 and 35.3 mg of the methyl ester of 5b.

Molecular Weight:312.4
XLogP3:5.5
Hydrogen Bond Donor Count:2
Hydrogen Bond Acceptor Count:4
Rotatable Bond Count:16
Exact Mass:312.23005950
Monoisotopic Mass:312.23005950
Topological Polar Surface Area:74.6
Heavy Atom Count:22
Complexity:280
Defined Bond Stereocenter Count:1
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes