Conversion of unsaturated fatty acids — Nucleophilic additions to methyl (E)‐12‐Oxo‐10‐octadecenoate [1]

Abstract

Methyl ricinoleate is converted in 57% yield into methyl (E)-12-oxo-Umwandlung ungeslttigter Fettsluren -Nukleophile Additionen 10-octadecenoate (4) by oxidation of the 12-OH group and conjugaan (E)-l2-0xo-1O-octadecensauremethylester. Ricinolsauremetion of the double bond. The enone fatty acid methylester 4 reacts in thylester wird durch Oxidation der Hydroxylgruppe und Konjugation high yield with anions of 1,3-dicarbonyl compounds, nitroalkanes, der Doppelbindung mit 57% Ausbeute in (E)-12-0xo-10-octadecenacylanions from aromatic aldehydes and cyanide to new C10-funcsauremethylester (4) uberfuhrt. An den Enonfettsauremethylester 4 tionalized fatty acids. The nitroalkyl adducts can be converted into werden anionisierte 1,3-Dicarbonylverbindungen, Nitroaliphate, pyrroloid and furanoid fatty acids. Acylanionen aus aromatischen Aldehyden und das Cyanidanion zu neuen C10-funktionalisierten Fettsauren in hohen Ausbeuten addiert. Die Nitroalkyladdukte lassen sich in Pyrrol-und Furanfettsauren umwandeln.

Conversion of unsaturated fatty acids - cycloadditions with unsaturated fatty acids [1]

“…can be prepared from ricinoleic acid [14]. The double bond bearing an electron withdrawing substituent can possibly react as a fatty acid derived dienophile, a behaviour, which would nicely supplement the use of methyl conjuenate as a fatty acid derived diene.…”

“…Methyl (E) -12-oxo-10-octadecenoate (11) [14] and dienophiles with electron donating subsituents. 11 and 2-(trimethylsiloxy)-1,3-butadiene: 11 (360.0 mg, 1.16 mmol) and 2-(trimethylsiloxy)-1,3-butadiene (1.50 g, 10.5 mmol) dissolved in toluene (1 ml) were heated for 48 h to 140°C.…”

Electrochemical conversion of fatty acids

“…Methyl 12oxo-10-octadecenoate was obtained by first oxidation of methyl ricinoleate to the keto compound. Thereafter the double bond was conjugated to the carbonyl group by acid catalysis (Scheme 8b) [37]. The cathodic reduction of the enones in dimethyl formamide afforded in good yield and selectivity the corresponding hydrodimers: the C 22 -diester 39 and the dimer 40 of a C 18 -fatty acid (Scheme 9a and b) [38,39].…”

Catalytic C,C-Bond Forming Additions to Unsaturated Fatty Compounds

“…If the double bond is conjugated to a carbonyl group, the vinylogous addition of nucleophiles to the double bond becomes possible. Interesting new oleochemicals were synthesized from unsaturated fatty compounds by Michael additions [56,57]. Allylic carbonates were found to be very good substrates for the nucleophilic substitution by palladium(0)-catalysis [58].…”

“…palladium(0)-catalyzed substitution to unsaturated fatty acids, they had to be converted into the respective allyl carbonates. Michael acceptors derived from fats can be synthesized in different ways, but only the substoichiometric oxidation with selenium dioxide was found to work satisfactorily [56]. The corresponding reactions of methyl 10-undecenoate 6b and methyl oleate 1b afforded the allylic alcohols methyl 9-hydroxy-10-undecenoate 9 and methyl 12-hydroxyoctadec-10-enoate 10 (mixture of regioisomers), respectively.…”