Methyl undecylenate

It can be obtained from castor oil. Methanolysis of castor oil yields methylester of ricinoleic acid. Pyrolysis at 500°C forms n-heotaldehyde and methyl-undecylenate. Hydrolysis of latter... 

The a-diazo ester 32 with its y-branching was designed to minimize / -hydride elimination. The reaction of a-diazo methyl undecylenate 44 (Eq. 1) with Rh2(Oct)4 (42b) gave an I/A ratio of 2.8, while reaction with Rh2(MPPlM)4 (42i) gave only the /1-hydride elimination product 45. 

SYNS METHYL 9-UNDECENOATE METHYL 10-UNDECENOATE METHYL UNDECYLENATE... 

It is possible to form rings from long chain di-olefins but, as with esterification of hydroxy acids, high dilution conditions must be employed. An example (Jap. Patent, 2003) is the formation of the lactone analogue of muscone shown in Figure 4.60. This synthesis takes advantage of the ready availability of methyl undecylenate from castor oil. 

The long-chain structure by itself, as exemplified by n-aliphatic hydrocarbons, shows no extreme-pressure lubricant functionality. Evidently the additive action is connected with the carboxylate ester and the sulfide structures. To demonstrate this, Dorinson isolated an ester/ sulfide component from sulfurized methyl undecylenate, identified its structure, synthesized an organosulfide-ester with this structure, and showed that the lubricant additive activity was the same for the fraction separated from sulfurized methyl undecylenate end for the synthetic material. The data, summarized ib Fig. 11-15, were obtained tiy pin-and-disk wear tests with hardened steel rubbing specimens and show the effect of contact pressure on the depth-rate of wear. The significant feature is the change from a low rate of wear, relatively insensitive to increase of pressure in the range 0.276-1.724 GPa (40,000-250,000 Ib/in ), to pressure-sensitive increase of wear rate at 1.724 GPa and higher. 

Figure 11-15. Sulfurized fatty esters as extreme-pressure additives. Pin and disk wear test at 85.85 cm/s with hardened steel. I Sulfurized methyl undecylenate, 1.22% S in lubricant. II Sulfurized methyl un-...

The pyrolysis step is not particularly efficient at yielding methyl undecylenate [7] straightforward techniques lead to low yields of 17-35% whereas newer techniques can reach values between 45-50%. By including these process values and starting chemical composition, the overall yield to undecenoic acid is rather low 15-20% of the original castor bean mass. 

Nylon 11 was originally synthesized in France. The monomer, cy-aminoundecanoic acid, is obtained from methyl ricinoleate that comes from castor oil. Methyl ricinoleate is first cleaved thermally to heptaldehyde and methyl undecylenate ... 

CAS 1731-86-8 EINECS/ELINCS 217-053-2 Synonyms Methyl N-undecanoate Methyl undecylenate Undecanoic acid methyl ester n-Undecanoic acid methyl ester... 

Synonyms Methyl undecylenate 9-Undecenoic acid, methyl ester... 

Methyl undecylenate. See Methyl 9-undecenoate Methyl undecanoate Methyl undecyf ketone. See 2-Tridecanone Methyl 2-undecynoate CAS 10522-18-6 FEMA 2751... 

The heptanol (enanthol), which occurs on scission, is used for many different syntheses. The methyl undecylenate is saponified to the acid, to which hydrogen bromide is added across the double bond in an 02 initiated radical reaction to produce undecanoic acid. This is converted to 11-amino undecanoic acid by ammonolysis in aqueous dispersions, to which pure 11-bromoundecanoic acid can be added, since 10-bromoundecanoic acid cannot be ammonolyzed because of the secondary Br atom. Use of 3 kg of castor oil produces about 1 kg of nylon 11. 

In the first step, the pyrolysis of methyl ricinoleate is carried out at about 500°C the principal products are n-heptaldehyde and methyl undecylenate. The latter is hydrolyzed to give undecylenic acid which is treated with hydrogen bromide in a non-polar solvent in the presence of a peroxide. Under these conditions, reverse Markownikoff addition occurs and the main product is cj-bromoundecanoic acid. This product is then treated with ammonia to give co-aminoundecanoic acid, which is a crystalline solid, m.p. 189°C. 

Ross et also studied the reaction of methyl undecylenate 11 with MA. The product was a mixture of diastereomers of 12 identified as the trimethyl ester derivative. Tamayo et have also examined various unsaturated esters. Results of MA reaction with some unsaturated esters are shown in Table 5.2. 

Methylstyrene, MA copolymerization, 373, 374 Methylsuccinic anhydride, hydrolysis rate, 74 3-Methylthiophene, MA copolymerization, 536 Methyl undecylenate MA ene adduct, 151, 152 MA ene reaction, 152... 

---