The invention relates to a process for the synthesis of diacids or diesters of general formula ROOC—(CH2)x—COOR, in which n is an integer between 5 and 14, R is either H or an alkyl radical of 1 to 4 carbon atoms, from natural long-chain monounsaturated fatty acids or esters including at least 10 adjacent carbon atoms per molecule of the general formula CH3—(CH2)n—CHR1—CH2—CH═CH—(CH2)p—COOR, in which R is H or an alkyl radical with 1 to 4 carbon atoms, R1 is either H or OH, and n and p, which are equal or different and are indices between 2 and 11. The method comprises: during a first step, converting the natural fatty acid or ester by pyrolysis or by ethenolysis, into a ω-monounsaturated fatty acid or ester of the general formula CH2═CH—(CH2)m—COOR, in which m is equal to p or p+1, depending on the nature of the processed fatty acid/ester and the conversion used; during a second step, submitting the product thus obtained to a metathesis or homometathesis reaction for obtaining a compound of the general formula ROOC—(CH2)m—CH═CH—(CH2)m—COOR, or cross-metathesis with a compound of formula R2OOC—(CH2)r—CH═CH—R3, in which R2 is either H or an alkyl radical front with 1 to 4 carbon atoms, r is either 0 or 1 or 2 and R3 is H, CH3 or COOR2, thus defining a cyclic or molecule or not, in order to obtain an unsaturated compound of the general formula ROOC—(CH2)m—CH═CH—(CH2)r—COOR2, and during a third step, converting the unsaturated compound into a saturated compound by hydrogenation of the double bond.

Title
Method for the synthesis of diacids or diesters from natural fatty acids and/or esters
Application Number
12/664182
Publication Number
20100305354
Application Date
June 11, 2008
Publication Date
December 2, 2010
Inventor
Jean Luc Dubois
Agent
Patent Department 26th Floor
PA, US
Arkema
PA, US
Assignee
Arkema France
IPC
C07C 69/52
C07C 51/21
C07C 67/04
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