Ricinolic acid methyl ester
Transesterification of castor oil to ricinoleic acid methyl ester
see synthesis...............http://kriemhild.uft.uni-bremen.de/nop/en/instructions/pdf/4001_en.pdf
http://pubs.rsc.org/en/content/articlelanding/2012/ra/c2ra22499b/unauth#!divAbstract
http://pubs.rsc.org/en/content/articlelanding/2012/ra/c2ra22499b/unauth#!divAbstract
| 1H-NMR: Ricinolic acid methyl ester | |||
| 300 MHz, CDCl3 | |||
| delta [ppm] | mult. | atoms | assignment |
| 0.84 | t | 3 H | 18-CH3 |
| 1.24 | m | 16 H | CH2 |
| 1.41 | m | 2 H | 13-CH2 |
| 1.59 | m | 2 H | 3-CH2 |
| 2.02 | m | 2 H | 8-CH2 |
| 2.09 | s | 1 H | OH |
| 2.19 | m | 2 H | 11-CH2 |
| 2.28 | t | 2 H | 2-CH2 |
| 3.59 | m | 1 H | 12-CH |
| 3.61 | s | 3 H | OCH3 |
| 5.35 | m | 1 H | 9-CH |
| 5.49 | m | 1 H | 10-CH |
The prime example of an unsaturated hydroxy fatty acid is probably ricinoleic (12-hydroxy-octadeca-9-enoic) acid, the major fatty acid in castor oil, which contains a hydroxy group in the homoallylic position (3(Z)-enol). The C20 analogue of ricinoleic acid is lesqueroleic acid obtained from lesquerella oil. The proton NMR spectrum of the methyl ester of ricinoleic acid is shown in Figure 4. Due to the proximity of the hydroxy group to the double bond, the signal of the olefinic protons is split, with the downfield signal assigned to the proton at C9 and the upfield signal to the proton at C-10 (Lie Ken Jie and Cheng, 1993). The signal (quintet) of the proton at C12 is observed slightly upfield at about 3.65 ppm of the methyl ester signal, even slightly overlapping it. Again the protons at C2 are found at about 2.3 ppm. The presence of the hydroxy group causes the signals of the allylic protons to split compared to methyl oleate. The signals of the protons at C11 and C8 are observed at 2.20 and 2.05 ppm, respectively. The signals of the other protons are contained in the broad methylene signal, with the peaks of the protons at C3 and C13 being at the downfield end.
| 13C-NMR: Ricinolic acid methyl ester | |||
| 75.5 MHz, CDCl3 | |||
| delta [ppm] | assignment | ||
| 13.8 | C18 | ||
| 22.4 | C17 | ||
| 33.8 | C2 | ||
| 35.2 | C13 | ||
| 36.7 | C11 | ||
| 51.1 | OCH3 | ||
| 71.2 | C12 | ||
| 125.3 | C9 | ||
| 132.6 | C10 | ||
| 174.0 | C1 (C=O) | ||
| 76.5-77.5 | CDCl3 | ||
| GC: pure product | |
| column | DB-1 L=28 m, d=0.32 mm, film=0.25 µm |
| inlet | on column injection |
| carrier gas | H2, 40 cm/s |
| oven | 90°C (5 min), 10°C/min --> 240°C (20 min) |
| detector | FID, 270°C |
| integration | percent concentration calculated from relative peak area |
Substances produced |
| Products | Amount | Risk | Safety | ||
|---|---|---|---|---|---|
| Ricinolic acid methyl ester | 100 g | R no data | S no data | ||
| Glycerol | R | S | |||
| Byproducts | Amount | Risk | Safety | ||
| Palmitic acid methyl ester | R | S | |||
| Stearic acid methyl ester | R | S | |||
| Oleic acid methyl ester | R - | S - | |||
| Linoleic acid methyl ester | R - | S - |
| Waste | Disposal |
|---|---|
| aqueous phase after shaking out | solvent water mixtures, halogen free |
| distilled methanol | solvents for rectification |
| distilled petroleum ether | solvents for rectification |
| sodium sulfate | solid waste, free from mercury |
| glycerol from separating funnel | organic solvents, halogen free |
Data availability |
| Toxicity and Ecotoxicity data | Only toxicity data | Neither toxicity nor ecotoxicity data | Not even a CAS Nr |
|
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Substances required |
| Educts | Amount | Risk | Safety | |||||
|---|---|---|---|---|---|---|---|---|
| Castor oil |
| 10 g | R 36/38 | S 24/25-26-36 | ||||
| Methanol |
| 40 mL | R 11-23/24/25-39/23/24/25 | S 1/2-7-16-36/37-45 | ||||
| Catalyst | Amount | Risk | Safety | |||||
| Sodium methylate 16% in methanol |
| 0.3 mL | R 11-14-34 | S 8-16-26-43-45 | ||||
| Solvents | Amount | Risk | Safety | |||||
| Petroleum ether (60-80) |
| 40 mL | R 11-38-48/20-52/53-62-65 | S 9-16-23.2-24-29-33-36/37-62 | ||||
| Water | ~ 80 mL | R | S | |||||
| Others | Amount | Risk | Safety | |||||
| Sodium sulfate |
| ~1 g | R 36/37/38 | S 26-36 | ||||
| Solvents for analysis | Amount | Risk | Safety | |||||
| Dichloromethane |
| R 40 | S 2-23.1-24/25-36/37 | |||||
| Acetic acid ethyl ester |
| R 11-36-66-67 | S 2-16-26-33 | |||||
| Petroleum ether (60-80) |
| R 11-38-48/20-52/53-62-65 | S 9-16-23.2-24-29-33-36/37-62 |
Equipment |
 | two-necked flask 1000 mL |  | magnetic stirrer with magnetic stir bar | |
 | separating funnel |  | rotary evaporator |
Simple evaluation indices |
| No density available for catalyst 1 |
| Atom economy | not defined | ||
| Yield | not defined | ||
| Target product mass | 100 | g | |
| Sum of input masses | ? | g | |
| Mass efficiency | ? | mg/g | |
| Mass index | ? | g input / g product | |
| E factor | ? | g waste / g product |
more...................
http://macroheterocycles.isuct.ru/en/annot/t06n02/180
acid nmr
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