US 2014O155647A1 (19) United States (12) Patent Application Publication (10) Pub. No.: US 2014/0155647 A1 Dubois (43) Pub. Date: Jun. 5, 2014

(54) METHOD FOR THE SYNTHESIS OF DIACIDS Publication Classification OR DESTERS FROMINATURAL FATTY ACDS AND/ORESTERS (51) Int. Cl. C07C 67/303 (2006.01) (71) Applicant: Arkema France, Colombes (FR) CD7C5L/36 (2006.01) (52) U.S. Cl. (72) Inventor: Jean-Luc Dubois, Millery (FR) CPC ...... C07C 67/303 (2013.01); C07C 51/36 (2013.01) (21) Appl. No.: 13/946,292 USPC ...... 560/190; 562/592 (57) ABSTRACT (22) Filed: Jul.19, 2013 Disclosed herein a process for the synthesis of diacids or diesters of general formula ROOC (CH)x-COOR, in O O which in represents an integer between 5 and 14 and R is either Related U.S. Application Data H or an alkyl radical of 1 to 4 carbon atoms, starting from (63) Continuation of application No. 12/664,182, filed on long-chain natural monounsaturated fatty acids or Apr. 21, 2010, now abandoned, filed as application No. comprising at least 10 adjacent carbonatoms per molecule, of PCT/FR2008/051038 on Jun. 11, 2008. formula CH (CH)n-CHR—CH2—CH=CH-(CH2)p- COOR, in which R represents Horan alkyl radical compris (30) Foreign Application Priority Data ing from 1 to 4 carbon atoms, R is either H or OH, and n and p, which are identical or different, are indices between 2 and Jun. 13, 2007 (FR) ...... O755733 11. US 2014/O 155647 A1 Jun. 5, 2014

METHOD FOR THE SYNTHESIS OF DACDS -continued OR DESTERS FROMINATURAL FATTY ACDS AND/ORESTERS 0001. The invention is targeted at a process for the synthe OH sis by metathesis of Saturated long-chain diacids or diesters OH starting from a monounsaturated or fatty which is either natural or originates from the direct conver sion of a natural . 0002 Diacids are obtained industrially by various meth Adipic acid ods, all of which, however, exhibit some disadvantages. A great variety of these methods is enlarged upon in the Kirk Othmer Encyclopedia, Vol. A8, pages 523-539. 0003. It is possible to distinguish therein methods by deg radation, such as oZonolysis or oxidation, of vegetable fatty 0004. The ozonolysis of , of and acids. of makes it possible to respectively produce the diacids comprising 9, 6 and 13 carbonatoms according to the OH above reaction process for petroselinic acid. 0005. Another example is the cleavage of ricinoleic acid -n-n-n-n-n-N---so by the action of sodium hydroxide at a temperature of greater Petroselinic acid than 180°C. This method, used industrially, makes it possible to obtain the diacid comprising 10 carbon atoms. The same method, as illustrated in the scheme below, can be OH applied to lesquerolic acid and results in the formation of a diacid comprising 12 carbon atoms. This method exhibits the advantage of using renewable start ing materials but is restricted essentially to the Co diacid, -- lesquerolic acid being still not very widespread, and thus this method is relatively little used.

OH

OH

CH Ricinoleic acid

OR OH

OH N

CH Lesquerolic acid NaOH, 180-250° / Not 2500 C. US 2014/O 155647 A1 Jun. 5, 2014

-continued O OH ~~~~~ O OH O OR OH O OR ~~~~. OH OH -- O O ~~~~ OH CH3 OH

--~~~ CH

0006 Mention may also be made of the oxidative degra acids oleic (cis-9-octadecenoic) acid, elaidic (trans-9-octade dation of monocarboxylic acids by the action of NO. The cenoic) acid, petroselinic (cis-6-octadecenoic) acid, vaccenic oxidation of makes it possible to obtain a mixture (cis-11-octadecenoic) acid and ricinoleic (12-hydroxy-cis-9- of sebacic acid and of ; Suberic acid can be octadecenoic) acid, the Co acids gadoleic (cis-9-eicosenoic) obtained from . acid, gondoic (cis-11-eicosenoic) acid, cis-5-eicosenoic acid 0007. It is also possible to obtain diacids from smaller and lesquerolic (14-hydroxy-cis-11-eicosenoic) acid, and the molecules by using variant techniques of carbonylation. C. acids cetoleic (cis-11-docosenoic) acid and erucic (cis 0008 Finally, mention may be made of the bacterial fer 13-docosenoic) acid. mentation of paraffins, a well known method which makes it 0014. These various acids result from the vegetable possible to obtain numerous diacids of variable chain length. extracted from various plants, such as Sunflower, rape, castor However, this method does not make it possible to obtain oil plant, bladderpod, olive, soya, palm tree, coriander, celery, diacids with a length of greater than 16 carbon atoms as the dill, carrot, fennel or Limnanthes alba (meadowfoam). paraffins then have a melting point which is far too high for 0015 They also result from the terrestrial or marine ani conversion to be possible. Another major disadvantage is that mal world and, in the latter case, both in the form of fish or the bacteria consume a portion of the paraffins in order to mammals, on the one hand, and of algae, on the other hand. provide for their growth, resulting in low yields and in the They are in general originating from ruminants, from fish, need to purify the products. Such as the cod, or from marine mammals, such as whales or 0009. In the polymer industry, in particular for the produc dolphins. tion of polyamides of diacids/diamines type or of industrial polymers, it is necessary to have available a whole range of 0016. The invention is targeted at a process for the synthe diacids as starting materials, which diacids can in addition be sis of diacids or diesters of general formula ROOC (CH) converted to diamines of the same chain length by a simple COOR, in which X represents an integer between 5 and 24 chemical reaction. and R is either H or an alkyl radical of 1 to 4 carbon atoms, starting from long-chain natural monounsaturated fatty acids 0010. It is therefore necessary to find a type of process or esters comprising at least 10 adjacent carbon atoms per which makes it possible to obtain a virtually complete range molecule, of formula CH (CH), CHR CH of diacids and which, in addition, uses renewable materials of CH=CH-(CH2). COOR, in which R represents Horan natural origin. alkyl radical comprising from 1 to 4 carbonatoms, R is either 0011. The object of the invention is a process for the pro H or OH, and n and p, which are identical or different, are duction of a whole range of Saturated diacids or diesters of indices between 2 and 11, preferably between 3 and 11, which general formula ROOC (CH), COOR starting from fatty consists, in a first stage, in converting said natural fatty acid or acids of natural origin. ester, either by pyrolysis or by ethenolysis (ethylene cross 0012. The solution provided consists in carrying out the metathesis), into an W-monounsaturated fatty acid or ester of operation starting from long-chain natural monounsaturated general formula CH2=CH-(CH2), COOR, in which mis fatty acids. Long-chain natural fatty acid is understood to equal to p or p--1, depending on the nature of the fatty acid/ mean an acid resulting from plant or animal sources, includ ester treated and the conversion used, ethenolysis or pyroly ing algae, more generally from the plant kingdom, which are sis, then, in a second stage, in Subjecting the product thus thus renewable, comprising at least 10 and preferably at least obtained to a metathesis reaction, either homometathesis, in 14 carbon atoms per molecule. order to obtain a compound of formula ROOC (CH), 0013 Mention may be made, as examples of such acids, of CH=CH-(CH), COOR, or cross-metathesis with a the Co acids obtusilic (cis-4-decenoic) acid and caproleic compound of formula ROOC (CH), CH=CH-R, in (cis-9-decenoic) acid, the C acids lauroleic (cis-5-dode which R is either Horan alkyl radical comprising from 1 to cenoic) acid and linderic (cis-4-dodecenoic) acid, the Ca 4 carbon atoms, r is either 0 or 1 or 2 and R is H, CH or acids myristoleic (cis-9-tetradecenoic) acid, physeteric (cis COOR, in the last case forming a cyclic or noncyclic mol 5-tetradecenoic) acid and tsuZuic (cis-4-tetradecenoic) acid, ecule, in order to obtain an unsaturated compound of formula the C acid palmitoleic (cis-9-hexadecenoic) acid, the Cs ROOC (CH), CH=CH-(CH), COOR, and then, US 2014/O 155647 A1 Jun. 5, 2014

in a third stage, in finally converting, by hydrogenation of the acid, both oleic acid and ; and rapeseed oil com double bond, the unsaturated compound to give a saturated prises, in addition to oleic acid, simultaneously linoleic acid, compound. linolenic acid and . The presence of these diun 0017. The natural monounsaturated fatty acid or ester of saturated or polyunsaturated acids is not of major conse general formula CH (CH), CHOH-CH CH=CH-(CH2). COOR can be subjected to a pyrolysis quence with regard to the progression of the process insofar reaction. as, during the first stage, in the case of ethenolysis, linoleic 0018. The acid or the ester of formula CH=CH-(CH) acid will also form the w-monounsaturated fatty acid of gen —COOR resulting from the first stage can be subjected to eral formula CH2=CH (CH), COOR, with minor a homometathesis, the product of which, ROOC (CH.) amounts of short dienes and of C-olefins. In the case of 1 CH=CH-(CH2). COOR, is hydrogenated. ricinoleic acid, the pyrolysis reaction will not convert these 0019. The acid or the ester of formula CH=CH-(CH) similar acids. —COOR resulting from the first stage can be subjected to 0028. Examples of the synthesis of diacids are given a cross-metathesis, the product of which obtained is hydro below. All the mechanisms detailed below illustrate, in order genated. to facilitate the account, the acid formed. However, the met 0020. The natural monounsaturated fatty acid or ester of athesis is also effective with an ester and even often more general formula CH (CH), CHOH CH effective, the medium generally being more anhydrous. In the CH=CH-(CH2). COOR can be subjected to an ethenoly same way, the schemes illustrate reactions with the cis isomer sis reaction. of the acids (or esters); the mechanisms are also clearly appli cable to the trans isomers. 0021. The acid or the ester of formula CH=CH-(CH) COOR resulting from the first stage can be subjected to a 0029. The C diacid can be obtained from obtusilic (cis 4-decenoic) acid, linderic (cis-4-dodecenoic) acid and tsu homometathesis, the product of which, ROOC (CH.) Zuic (cis-4-tetradecenoic) acid by carrying out an ethenolysis CH=CH-(CH2). COOR, is hydrogenated. in the first stage, followed by a cross-metathesis with acrylic 0022. The acid or the ester of formula CH=CH-(CH) acid and then hydrogenation. COOR resulting from the first stage can be subjected to a cross-metathesis, the product of which obtained is hydroge 0030 The C, diacid can be obtained from lauroleic (cis nated. 5-dodecenoic) acid and physeteric (cis-5-tetradecenoic) acid by an ethenolysis in the first stage, followed by a cross 0023 The cross-metathesis is carried out with acrylic acid metathesis with acrylic acid and then hydrogenation. when R=H, X=0 and R=H. In the case where x=1, R=H and R=CH, the compound is HOOC CH-CH=CH 0031. The Cs diacid can be obtained from obtusilic (cis CH and is obtained, for example, by hydroxycarbonylation 4-decenoic) acid, linderic (cis-4-dodecenoic) acid and tsu Zuic (cis-4-tetradecenoic) acid by carrying out an ethenolysis of butadiene. In this case, during the cross-metathesis, pro in the first stage, followed by a homometathesis, or from pylene is produced and is removed from the reaction medium. petroselinic acid by ethenolysis in the first stage, followed by 0024 Preferably, when R is COOR, ROOC-(CH), a cross-metathesis with acrylic acid, in both cases brought to CH=CH R is a symmetrical molecule with r=0. When R. completion by a hydrogenation. is CH ROOC (CH), CH=CH-R reacts with a fatty 0032. The Codiacid can be obtained from lauroleic (cis acid by cross-metathesis and the reaction results in a diacid 5-dodecenoic) acid and physeteric (cis-5-tetradecenoic) acid and a shorter fatty acid but also in propylene. The propylene by an ethenolysis in the first stage, followed by homomet is removed as it is formed from the reaction medium, which athesis finished off by the hydrogenation. displaces the reaction towards the desired products. 0033. The C diacid can be obtained from oleic (cis-9- 0025. When ROOC-(CH), CH=CH-COOR, octadecenoic) acid, elaidic (trans-9-octadecenoic) acid, forms a cyclic molecule. Such as maleic anhydride, then the gadoleic (cis-9-eicosenoic) acid and myristoleic (cis-9-tet cross-metathesis results in an unsaturated fatty acid also com radecenoic) acid with an ethenolysis in the first stage, fol lowed by a cross-metathesis with acrylic acid, in each case prising an anhydride functional group. The diacid and the brought to completion by a hydrogenation. In the case of oleic fatty acid can be released by hydrolysis. acid, the following reaction process will be employed: 0026. In the process of the invention, the fatty acid can be treated either in its acid form or in its ester form. The change CH=CH (> CH=CH-(CH), COOH+ from one form to the other is carried out by methenolysis, CH=CH-(CH2).7 CH 1) esterification or hydrolysis. CH=CH-(CH2), COOH-HOOC-CH=CH 0027. In the process of the invention, use is made of fatty <> HOOC CH-CH (CH), COOH+ acids or esters of natural origin, that is to say present in CH2=CH2 2) extracted oils or fats. The latter are in fact composed, in addition to the ester or acid participating in the reaction, of a HOOC-CH=CH-(CH), COOH--H->HOOC mixture of esters or acids with similar formulae. By way of (CH2)o-COOH 3) examples, palm oil comprises, in addition to oleic acid, 0034. The reaction mechanism for this reaction is, in its linoleic acid; castor oil comprises, in addition to ricinoleic various alternative forms, illustrated by scheme 1 below US 2014/O 155647 A1 Jun. 5, 2014

-continued O Scheme 1

O

O R R -- O1 a- -- CH2 O1 R

N O MCH HC O

O

H HO H3C + H2 --

HO CH S O CH O

O

CH H HC

O OH

HO 0035. The C diacid can be obtained from petroselinic acid and ricinoleic acid according to two different reaction mechanisms. Petroselinic (cis-6-octadecenoic) acid is con verted by an ethenolysis in the first stage, followed by a homometathesis, finished off by the hydrogenation. Ricino leic (12-hydroxy-cis-9-octadecenoic) acidis, for its part, Sub jected to a pyrolysis which makes possible the synthesis of ()-undecenoic acid, which is subjected to a cross-metathesis with acrylic acid giving 11-dodecenedioic acid, converted by hydrogenation to dodecanedioic acid. 0036. The reaction mechanism for this reaction with petroselinic acid (scheme 2) is as follows. CH2 CH -(CH2)o CH=CH-(CH2). COOH US 2014/O 155647 A1 Jun. 5, 2014

Hosts, coot 3) CH -continued CH 2-> 210 2 2 2 2

Scheme 2 -- O1 R

O O OH O OH O HO

--

OH -- O HCV CH OH

O / --

R O

HO OH O1 R O

O H2 ->

O

HO CH CH -- CH2| - -- 0037. The reaction process with- ricinoleic- - - - acid- - is- as fol 2CH2 lows:

CH=CH-(CH2)COOH-HOOC-CH=CH

HOOC-CH=CH-(CH-)s COOH--H->HOOC (CH2)o-COOH. 3) 0038. The C diacid can also be obtained by ethenolysis of oleic acid, to give the unsaturated acid CH=CH-(CH2) 7—COOH, followed by a cross-metathesis with the acid R CH CH=CH-CH COOH and, finally, by a hydroge nation. 0039. The C diacid can be obtained from vaccenic (cis 11-octadecenoic) acid, gondoic (cis-1'-eicosenoic) acid and cetoleic (cis-1'-docosenoic) acid with an ethenolysis in the US 2014/O 155647 A1 Jun. 5, 2014 first stage, followed by a cross-metathesis withacrylic acid, in at a pressure of 1 to 30 bar in the presence of a conventional each case brought to completion by a hydrogenation. metathesis catalyst. The reaction time is chosen according to 0040. The Ca diacid can be obtained from lesquerolic the reactants employed and in order to reach, to the nearest acid with a pyrolysis of the hydroxylated fatty acid to form the point, the equilibrium of the reaction. The reaction is carried acid of formula CH2=CH (CH) COOCH, followed out under an ethylene pressure. by a cross-metathesis with acrylic acid and, finally, by a 0049. The pyrolysis reaction of the first stage is carried out hydrogenation. It can also be obtained by ethenolysis of vac at a temperature generally of between 400 and 600° C. cenic acid, to give the unsaturated acid CH2=CH-(CH2) 0050. The homometathesis reaction of the second stage is COOH, followed by a cross-metathesis with the acid carried out at a temperature generally of between 20 and 200° CH-CH=CH-CH COOH and, finally, by a hydroge C. in the presence of a conventional metathesis catalyst. nation. 0051. The cross-metathesis reaction of the second stage is 0041. The Cs diacid can be obtained from erucic acid carried out at a temperature generally of between 20 and 200° with an ethenolysis in the first stage, followed by a cross C. in the presence of a ruthenium-based catalyst. metathesis with acrylic acid, brought to completion by a 0.052 The hydrogenation reaction of the third stage is hydrogenation. carried out at a temperature generally of between 20 and 300° 0042. The C diacid can be obtained from C. under hydrogen pressure in the presence of a catalyst with an ethenolysis in the first stage, followed by a cross comprising, for example, nickel, cobalt, platinum or palla metathesis with acrylic acid, brought to completion by a dium, and the like. The process of the invention is illustrated hydrogenation. by the following examples. 0043. It is entirely possible, if need be, to manufacture higher diacids by employing the process of the invention, for EXAMPLE 1. example C1s, C20, C22 or C26 diacids. 0053. This example illustrates the synthesis of the C 0044) The invention also relates to a process for the syn diacid starting from oleic acid. In a first stage, the ethenolysis thesis of the diacid or the diester of formula ROOC (CH) of oleic acid is carried out at 30° C. in the presence of a s COOR from 5-lauroleic or 5-physeteric acidorester with, tungsten-based catalyst in order to obtain 9-decenoic acid in the first stage, an ethenolysis of said acid or said ester, to CH=CH (CH), COOH. For the second stage, use is produce the acid or the ester of formula CH2=CH-(CH2) made of the bispyridine ruthenium complex (8) catalyst COOR, followed by a homometathesis, finished off by described in the publication by Chen-Xi Bei et al., Tetrahe hydrogenation. dron Letters, 46 (2005), 7225-7228, in carrying out the cross 0045 Metathesis reactions have been known for a long metathesis of 9-decenoic acid with methyl acrylate. The reac time, even if their industrial applications are relatively lim tion is carried out in CHCl, at a 0.1M 9-decenoic acid ited. Reference may be made, with regard to their use in the concentration and a 0.2M methyl acrylate concentration, at a conversion of fatty acids (esters), to the paper by J. C. Mol, temperature of 50° C. and for 12 hours. The yields are deter “Catalytic metathesis of unsaturated fatty acid esters and oil', mined by chromatographic analysis. In the present case, use which appeared in Topics in Catalysis, Vol. 27, Nos. 1-4, is made of 2 equivalents of methyl acrylate with respect to the February 2004 (Plenum Publishing Corporation). acid and with a catalyst concentration of 0.5 mol%. The yield 0046. The catalysis of the metathesis reaction has formed of product CH, OOC CH=CH-(CH), COOH is 50 the Subject of a great many studies and the development of mol%. This product can be hydrogenated according to a Sophisticated catalytic systems. Mention may be made, for conventional process with a yield of 100%. example, of the tungsten complexes developed by Schrocket al., J. Am. Chem. Soc., 108 (1986), 2771, or Basset et al., EXAMPLE 2 Angew. Chem. Ed. Engl., 31 (1992), 628. More recently, “Grubbs' catalysts, which are ruthenium-benzylidene com 0054. This example illustrates the synthesis of the Co plexes, have appeared (Grubbs et al., Angew. Chem. Ed. diacid starting from ricinoleic acid. During the first stage, Engl. 34 (1995), 2039, and Organic Lett. 1 (1999), 953). methyl ricinoleate is subjected to a pyrolysis at a temperature These relate to homogeneous catalysis. Heterogeneous cata of 550° C. to form methyl 10-undecenoate, which is con lysts have also been developed which are based on metals, verted to the acid form by hydrolysis. In the second homomet Such as rhenium, molybdenum and tungsten, deposited on athesis stage, use is made of the ruthenium complex (3) cata alumina or silica. Finally, studies have been carried out on the lyst described in the publication by Stefan Randlet al., Synlett preparation of immobilized catalysts, that is to say of cata (2001), 10, 430, which is very stable and does not decompose lysts whose active principle is that of the homogeneous cata when it is exposed to air or to water. The homometathesis lyst, in particular ruthenium-carbene complexes, but which is reaction is carried out in CHCl2, at a 0.15M 10-undecenoic immobilized on an inactive support. The object of these stud acid concentration, at a temperature of 30°C. and for 2 hours ies is to increase the selectivity of the reaction with regard to with a catalyst concentration of 0.5 mol%. The yields are the side reactions, such as "homometatheses', between the determined by chromatographic analysis. The yield of diacid reactants brought together. They relate not only to the struc HOOC-(CH) CH=CH-(CH) COOH is 67 mol ture of the catalysts but also to the effect of the reaction %. This product can be hydrogenated according to a conven medium and the additives which may be introduced. tional process with a yield of 100%. 0047 Any active and selective metathesis catalyst can be used in the process of the invention. However, use will pref EXAMPLE 3 erably be made of catalysts based on ruthenium and on rhe 0055. This example illustrates the synthesis of the C. nium. diacid starting from ricinoleic acid. The first stage is identical 0048. The ethenolysis (metathesis) reaction of the first to that of example 2, apart from the condition that it is the stage is carried out at a temperature of between 20 and 100° C. methyl ester of 10-undecenoic acid CH=CH-(CH) US 2014/O 155647 A1 Jun. 5, 2014

COOCH which is addressed in the second stage. This second stage is a cross-metathesis with methyl acrylate. Use is made, Homo- Cross for this reaction, of the bispyridine ruthenium complex (8) Methyl acry- meta- meta- Reac catalyst described in the publication by Chen-Xi Bai et al., Cata- late?methyl Conver- thesis thesis tion Org. Biomol. Chem. (2005), 3, 4139-4142. The reaction is Exam- lyst undecylenate Sion yield yield time carried out in CHCl, at a 0.05M methyl ester of 10-unde ple (mol%) molar ratio mol % mol % mol % min cenoic acid concentration and a 0.1M methyl acrylate con N A (1) O 98 100 O 30 centration, at a temperature of 30° C. and for 12 hours in the M B (1) O 95 100 O 30 presence of the catalyst at a concentration of 1 mol %, with O B (0.1) 10 99 O 99 30 respect to the methyl ester of 10-undecenoic acid. The yields are determined by chromatographic analysis. The yield of 1-11. (canceled) diester CH OOC CH=CH-(CH) COOCH is 70 12. A process for the synthesis of diacids or diesters of the mol%. This product, in its ester or acid form, can be hydro general formula ROOC (CH), COOR, in which X repre genated according to a conventional process with a yield of sents an integer between 5 and 24 and R is either Horan alkyl 100%. radical of 1 to 4 carbonatoms, starting from long-chain natu ral monounsaturated fatty acids or esters comprising at least 0056. This example thus illustrates a process for the syn 10 adjacent carbonatoms per molecule, of the formula CH thesis of the diester of formula CHOOC-(CH) (CH.),CHR CH-CH=CH-(CH.). COOR, in COOCH starting from the methyl ester of ricinoleic acid which R represents Horan alkyl radical comprising from 1 to Subjected, in the first stage, to a pyrolysis, in order to form the 4 carbon atoms, R is either H or OH, and n and p, which are ester of formula CH2=CH (CH) COOCH, which is identical or different, are indices between 3 and 11, which Subsequently Subjected to a cross-metathesis with methyl comprises: acrylate forming the diester of formula CHOOC converting said natural monounsaturated fatty acidorester, into an ()-monounsaturated fatty acid or ester of the CH=CH (CH) COOCH, which is subsequently general formula CH2=CH (CH), COOR, in hydrogenated. which m is equal to p or p--1, then, Subjecting the product thus obtained to cross-metathesis EXAMPLE 4 with a compound of the formula ROOC (CH), CH=CH-R in which R is either Horan alkyl radical 0057 The metathesis catalysts A and B were obtained comprising from 1 to 4 carbon atoms, r is either 0 or 1 or from Sigma Aldrich, catalogue references 56.9747 and 2 and R is H, CH or COOR, in the last case forming a cyclic or noncyclic molecule, to obtain an unsaturated 569755 respectively. These catalysts are also known as compound of the formula ROOC (CH), Grubbs catalyst, 2nd generation, and Hoveyda-Grubbs cata CH=CH (CH), COOR, and then, lyst, 2nd generation. converting, by hydrogenation, the unsaturated compound Catalyst A: benzylidener 1,3-bis(2,4,6-trimethylphenyl)-2- to a saturated compound. imidazolidinylidenedichloro(tri-cyclohexyphosphine)ru 13. The process as claimed in claim 12, wherein the con Verting said natural monounsaturated fatty acid or ester of thenium. general formula CH (CH), CHOH CH Catalyst B: (1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidi CH=CH-(CH2). COOR is via a pyrolysis reaction. nylidene)dichloro(o-isopropoxy-phenylmethylene)ruthe 14. The process as claimed in claim 13, wherein the co monounsaturated acid or the ester of formula CH2=CH nium. (CH2). COOR is subjected to a cross-metathesis, the Undecylenic acid is produced by Arkema by hydrolysis of the product of which is hydrogenated. methyl ester of undecylenic acid, itself obtained by cracking 15. The process as claimed in claim 12, wherein converting the methyl ester of ricinoleic acid. The latter is obtained by said natural monounsaturated fatty acid or ester of general transesterification of castor oil by in basic catalysis. formula CH (CH), CHOH-CH CH=CH-(CH) p—COOR is via an ethenolysis reaction. These products are produced in the Arkema factory at 16. The process as claimed in claim 15, wherein the co-mo Marseille Saint-Menet. nounsaturated acid or the ester of formula CH=CH-(CH2) In the experiments, 2.5g of ester of fatty acid (undecylenic COOR is subjected to a cross-metathesis, the product of acid) and/or an excess of methyl acrylate are used. Tetrade which is hydrogenated. 17. A process for the synthesis of a diester of the formula cane is used as internal standard. The reaction mixture is CHOOC-(CH) COOCH starting from the methyl stirred at 50° C. and degassed with argon. The catalyst is ester of ricinoleic acid comprising added to the solution, without addition of solvent. The pyrolysis, to form an ester of the formula CH=CH samples of reaction products are analyzed by chromatogra (CH2)s COOCH, and Subsequently cross-metathesis phy. with methyl acrylate to form a diester of the formula CHOOC-CH=CH-(CH) COOCH, which is 0058 Examples N and M below illustrate the case of the Subsequently hydrogenated. homometathesis of methyl undecylenate and example O 18. A process for the synthesis of the diester of the formula illustrates the case of the cross-metathesis of methyl unde CHOOC(CH) COOCH starting from the methyl ester cylenate and methyl acrylate. of lesquerolic acid comprising US 2014/O 155647 A1 Jun. 5, 2014

pyrolysis of the methyl ester of lesquerolic acid to forman ester of the formula CH2=CH (CH) COOCH, followed by cross-metathesis with methyl acrylate and thereafter hydrogenation. 19. A process for the synthesis of a diacid or diester of formula ROOC (CH) COOR starting from vaccenic acidorester comprising ethenolysis of the acidorester to give an unsaturated acidorester of the formula CH=CH-(CH2) COOR, followed by cross-metathesis with an acidorester of the formula CH-CH=CH-CH COOR and, there after hydrogenation.