Production of fatty olefin derivatives via olefin metathesis
In one aspect, the invention provides a method for synthesizing a fatty olefin derivative. The method includes: a) contacting an olefin according to Formula I with a metathesis reaction partner according to Formula IIb in the presence of a metathesis catalyst under conditions sufficient to form a metathesis product according to Formula IIIb: and b) converting the metathesis product to the fatty olefin derivative. Each R 1 is independently selected from H, C 1-18 alkyl, and C 2-18 alkenyl; R 2b is C 1-8 alkyl; subscript y is an integer ranging from 0 to 17; and subscript z is an integer ranging from 0 to 17. In certain embodiments, the metathesis catalyst is a tungsten catalyst or a molybdenum catalyst. In various embodiments, the fatty olefin derivative is a pheromone. Pheromone compositions and methods of using them are also described.
1. A method for synthesizing a fatty olefin derivative according to Formula VIb:
the method comprising:
i) reducing an alkyl ester according to Formula IIb
to form an alkenol according to Formula VIII
ii) acylating the alkenol to form an acylated alkenol according to Formula IX
and
iii) contacting the acylated alkenol with an olefin according to Formula I
in the presence of a metathesis catalyst having the formula:
under conditions sufficient to form the fatty olefin derivative; wherein:
R 1 is selected from the group consisting of H, C 1-18 alkyl, and C 2-18 alkenyl;
R 2b is C 1-8 alkyl,
R 2c is C 1-6 acyl,
subscript y is an integer ranging from 0 to 17; and
subscript z is an integer ranging from 0 to 17.
2. The method of claim 1 , wherein subscript y is 7.
3. The method of claim 1 , wherein R 1 is H, R 2b is methyl, R 2c is acetyl, subscript y is 7, and subscript z is 3.
4. The method of claim 1 , wherein the olefin according to Formula I is a linear C 3 -C 12 olefin, the alkyl ester according to Formula IIb is a Δ 9 -unsaturated fatty acid alkyl ester, and the fatty olefin derivative according to Formula VIb is an acetate ester of a C 11 -C 20 (Z)-9-fatty alcohol.
5. The method of claim 1 , wherein the catalyst is present in an amount less than 0.01 mol % with respect to the olefin or to the acylated alkenol.
6. The method of claim 1 , wherein the acylated alkenol is derived from a natural oil.
7. The method of claim 6 , wherein the natural oil is selected from the group consisting of canola oil, rapeseed oil, coconut oil, corn oil, cottonseed oil, olive oil, palm oil, peanut oil, safflower oil, sesame oil, soybean oil, sunflower oil, linseed oil, palm kernel oil, tung oil, jatropha oil, jojoba oil, mustard oil, pennycress oil, camelina oil, castor oil, and combinations thereof.