Ricinoleic acid structure

Castor oil [CO Structure (4.3)] is a triglyceride of ricinoleic (12-hydroxyoleic) acid about 90% of the fatty acid portion of the molecule consists of ricinoleic acid and 10% in the form of non-hydroxy acids consisting largely of oleic and linoleic acids. Small amounts of stearic and dihydroxystearic acids are also found in some industrial grades. 

Based on the postulated common metabolic pathway involved in DOD and TOD formation by PR3, it was assumed that palmitoleic acid containing a singular C9 cis double bond (a common structural property shared by oleic and ricinoleic acids), could be utilized by PR3 to produce hydroxy fatty acid. Bae et al. (2007) reported that palmitoleic acid could be utilized as a substrate for the production of hydroxy fatty acid by PR3. Structural analysis of the major product produced from palmitoleic acid by PR3 confirmed that strain PR3 could introduce two hydroxyl groups on carbon 7 and 9 with shifted migration of 9-cis double bond into 8-tram configuration, resulting in the formation of 7,10-dihydroxy-8( )-hexadecenoic acid (DHD) (Fig. 31.3).The time course study of DHD production showed that DHD formation was time-dependently increased, and peaked at 72 h after the addition of palmitoleic acid as substrate. However, production yield of DHD (23%) from palmitoleic acid was relatively low when compared to that of DOD (70%) from oleic acid (Hou and Bagby, 1991). 

Figure 3. Structure of poly(sebacic-co-ricinoleic acid) anhydride. Reproduced...

Figure 15. Schematic model of polymorphic structures of SRS and SLS. (a) A postulated structure of p forms of SRS, in which a ricinoleic acid leaflet is shown, (b) Polymorphic...

A unique vegetable oil is castor oil, extracted from the seeds of the plant Ricinus communis, which is a triglyceride of ricinoleic acid. Ricinoleic acid has 18 carbon atoms, a double bond (C9-C10) and a secondary hydroxyl group (C12) [29, 38, 41-43, 46]. The idealised structure of castor oil is shown in Figure 17.6. 

Figure 22.2 [A] General triglyceride structure and fatty acid percentage composition of common plant oil. [B] Fatty acids commonly used in polymer chemistry [a] oleic acid, [b] linoleic acid, (c) linolenic acid, [d] erucic acid, [e] petroselinic acid, [f] ricinoleic acid, [g] vernolic acid, [h] 10-undecenoic acid (reprinted with permission of Montero de Espinosa et al., 2011, Elsevier [10]].

Fig. 3.34 Chemical structures on ricinin and ricinoleic acid. (Authors own work)...

The best-known hydroxy acid is ricinoleic acid which is the major component of the readily available castor oil (Section 3.3.4). The structures of the natural hydroxy acids have been discussed in Section 1.9 where there is also an account of the occurrence of the less-common members. 

Ricinoleic acid, a compound that can be isolated from castor oil, has the structure CH3(CH2)5CH0HCH2CH = CH(CH2)7C02H. (a) How many stereoisomers of this structure are possible (b) Write these structures. 

Most contributions to the preparation of macromolecular materials derived from vegetable oils involve at least a modicum of chemical transformation, if not major modifications. The pancity of studies associated with their direct exploitation is due to the intrinsic mechanistic limitations of these pristine structures (with the possible exception of castor oil and ricinoleic acid) in terms of constructing as wide a variety of materials as required by the vast array of polymer applications. 

Other interesting structures belonging to this family of monomers were also synthesised by thiol-ene chemistry and by using ricinoleic acid (see Chapter 6). 

The fact that castor oil is a well-established industrial commodity because of the importance of some of its derivatives and macromolecular materials explains why so many studies on polymers derived from vegetable oils have focused on the use of ricinoleic acid, 10-undecenoic acid, and several other molecules based on their structures. Chapter 3 considered the context of direct polymerisation of this oil and its main fatty acid. This section is devoted to reviewing the most salient recent aspects of the vast realm of monomers and polymers based on their second-generation derivatives. Its treatment begins after the exhaustive review that Mutlu and Meier published in 2010 [124]. The impressive number of contributions since 2010 testifies to the relevance that this area has acquired. Some general notions are, however, needed to set the stage . 

Cramail and co-workers [40] described the synthesis of two linear and branched a,(0-diene monomers from castor and vernonia oils to develop linear low-density polyethylene and very low-density polyethylene-like polyesters. Methyl 10-undecenoate and 12-hydroxystearic acid, obtained from ricinoleic acid, were employed for the synthesis of the branched a,ro-diene, and a second monomer of similar structure (but linear) was synthesised from methyl 10-undecenoate and 1,12-dodecanediol (obtained from vernolic acid). Further ADMET copolymerisation of the dienes led to a series of copolyesters with Mn values of 14-62 kDa, Tm of 13.2-87.4 °C, and with various degrees of branching depending on the feed ratio between the two a,(0-dienes. 

Saponification of castor oil gives glycerol and mainly (80 to 90%) ricinoleic acid, also called 12-hydroxyoleic acid. Draw the structure of the main component of castor oil. 

Leadley et al (in preparation a) studied the surface chemistry of copolymers containing PSA and ricinoleic acid maleate (RAM), the general structure is shown... 

Leadley, S.R., Davdes, M.C., Domb, A., Nudelman, R., Paul, A.J. and Beamson, G. (in preparation a) The analysis of the surface chemical structure of anhydride copolymers of sebacic acid and ricinoleic acid maleate using XPS and ToF-SIMS. In preparation. 

Monomer(s) structure acids S-(p-carboxyphenoxy) valeric, 8-(p-carboxyphenoxy) ootanoic, 1,3-bis(p-carboxyphenoxy) propane, 1,6-bis(p-oarboxyphenoxy) hexane, 1,6-bis(o-carboxyphenoxy) hexane, adipic, azeiaic, dodecanedicarboxylic, dodecanedioic, fumaric, isophthaiic, p-carboxyphenoxy acetic, pimelic, sebacic, suberic, terephthalic other erucic acid dimer, ricinoleic acid maleate, ricinoleic acid succinate, 12-hydroxystearic acid succinate photopolymerizable monomers, e.g., methacrylated sebacic acid Goepferich, A Tessmar, J, Adv. Dmg Delivery Rev., 54,911-32, 2002 Jain, J P Chirkara, D Kumar, N, Expert Opin. Drug Deliv., 5, 8,889-907,2008. 

Ricinoleic acid, a compound that can be isolated from castor oil, has the structure CH3(CH2)5CH0HCH2CH=CH(CH2)7C02H. 

Hydroxy Fatty Acids. Ricinoleic acid is the best known of the straight-chain hydroxy fatty acids. Its structure is 12-OH, 18 1 (9). It is an optically active acid with a D(-i-)-configuration ... 

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