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Lauric acid
Names | |
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Preferred IUPAC name
Dodecanoic acid | |
Other names
n-Dodecanoic acid, Dodecylic acid, Dodecoic acid,
Laurostearic acid, Vulvic acid, 1-Undecanecarboxylic acid, Duodecylic acid, C12:0 (Lipid numbers)
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Identifiers | |
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3D model (JSmol)
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ChEBI | |
ChEMBL | |
ChemSpider |
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ECHA InfoCard | 100.005.075 |
EC Number |
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KEGG |
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PubChem CID
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UNII | |
CompTox Dashboard (EPA)
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Properties | |
C12H24O2 | |
Molar mass | 200.322 g·mol−1 |
Appearance | White powder |
Odor | Slight odor of bay oil |
Density | 1.007 g/cm3 (24 °C) 0.8744 g/cm3 (41.5 °C) 0.8679 g/cm3 (50 °C) |
Melting point | 43.8 °C (110.8 °F; 316.9 K) |
Boiling point | 297.9 °C (568.2 °F; 571.0 K) 282.5 °C (540.5 °F; 555.6 K) at 512 mmHg 225.1 °C (437.2 °F; 498.2 K) at 100 mmHg |
37 mg/L (0 °C) 55 mg/L (20 °C) 63 mg/L (30 °C) 72 mg/L (45 °C) 83 mg/L (100 °C) |
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Solubility | Soluble in alcohols, diethyl ether, phenyls, haloalkanes, acetates |
Solubility in methanol | 12.7 g/100 g (0 °C) 120 g/100 g (20 °C) 2250 g/100 g (40 °C) |
Solubility in acetone | 8.95 g/100 g (0 °C) 60.5 g/100 g (20 °C) 1590 g/100 g (40 °C) |
Solubility in ethyl acetate | 9.4 g/100 g (0 °C) 52 g/100 g (20°C) 1250 g/100 g (40°C) |
Solubility in toluene | 15.3 g/100 g (0 °C) 97 g/100 g (20°C) 1410 g/100 g (40°C) |
log P | 4.6 |
Vapor pressure | 2.13·10−6 kPa (25 °C) 0.42 kPa (150 °C) 6.67 kPa (210 °C) |
Acidity (pKa) | 5.3 (20 °C) |
Thermal conductivity | 0.442 W/m·K (solid) 0.1921 W/m·K (72.5 °C) 0.1748 W/m·K (106 °C) |
Refractive index (nD)
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1.423 (70 °C) 1.4183 (82 °C) |
Viscosity | 6.88 cP (50 °C) 5.37 cP (60 °C) |
Structure | |
Monoclinic (α-form) Triclinic, aP228 (γ-form) |
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P21/a, No. 14 (α-form) P1, No. 2 (γ-form) |
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2/m (α-form) 1 (γ-form) |
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a = 9.524 Å, b = 4.965 Å, c = 35.39 Å (α-form)
α = 90°, β = 129.22°, γ = 90°
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Thermochemistry | |
Heat capacity (C)
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404.28 J/mol·K |
Std enthalpy of
formation (ΔfH⦵298) |
−775.6 kJ/mol |
Std enthalpy of
combustion (ΔcH⦵298) |
7377 kJ/mol 7425.8 kJ/mol (292 K) |
Hazards | |
GHS labelling: | |
Danger | |
H412 | |
P273 | |
NFPA 704 (fire diamond) | |
Flash point | > 113 °C (235 °F; 386 K) |
Related compounds | |
Related compounds
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Glyceryl laurate |
Related compounds | |
Related compounds
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Undecanoic acid Tridecanoic acid Dodecanol Dodecanal Sodium lauryl sulfate |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Lauric acid, systematically dodecanoic acid, is a saturated fatty acid with a 12-carbon atom chain, thus having many properties of medium-chain fatty acids. It is a bright white, powdery solid with a faint odor of bay oil or soap. The salts and esters of lauric acid are known as laurates.
Occurrence
Lauric acid, as a component of triglycerides, comprises about half of the fatty-acid content in coconut milk, coconut oil, laurel oil, and palm kernel oil (not to be confused with palm oil), Otherwise, it is relatively uncommon. It is also found in human breast milk (6.2% of total fat), cow's milk (2.9%), and goat's milk (3.1%).
In various plants
- The palm tree Attalea speciosa, a species popularly known in Brazil as babassu – 50% in babassu oil
- Attalea cohune, the cohune palm (also rain tree, American oil palm, corozo palm or manaca palm) – 46.5% in cohune oil
- Astrocaryum murumuru (Arecaceae) a palm native to the Amazon – 47.5% in "murumuru butter"
- Coconut oil 49%
- Pycnanthus kombo (African nutmeg)
- Virola surinamensis (wild nutmeg) 7.8–11.5%
- Peach palm seed 10.4%
- Betel nut 9%
- Date palm seed 0.56–5.4%
- Macadamia nut 0.072–1.1%
- Plum 0.35–0.38%
- Watermelon seed 0.33%
- Viburnum opulus 0.24-0.33%
- Citrullus lanatus (egusi melon)
- Pumpkin flower 205 ppm, pumpkin seed 472 ppm
In Insects
- Black soldier fly Hermetia illucens 30–50 mg/100 mg fat.
Uses
Like many other fatty acids, lauric acid is inexpensive, has a long shelf-life, is nontoxic, and is safe to handle. It is used mainly for the production of soaps and cosmetics. For these purposes, lauric acid is reacted with sodium hydroxide to give sodium laurate, which is a soap. Most commonly, sodium laurate is obtained by saponification of various oils, such as coconut oil. These precursors give mixtures of sodium laurate and other soaps.
Lauric acid is a precursor to dilauroyl peroxide, a common initiator of polymerizations.
Nutritional and medical aspects
Although 95% of medium-chain triglycerides are absorbed through the portal vein, only 25–30% of lauric acid is absorbed through it.
Lauric acid increases total serum lipoproteins more than many other fatty acids, but mostly high-density lipoprotein (HDL). As a result, lauric acid has been characterized as having "a more favorable effect on total HDL than any other fatty acid [examined], either saturated or unsaturated". In general, a lower total/HDL serum lipoprotein ratio correlates with a decrease in atherosclerotic incidence. Nonetheless, an extensive meta-analysis on foods affecting the total LDL/serum lipoprotein ratio found in 2003 that the net effects of lauric acid on coronary artery disease outcomes remained uncertain. A 2016 review of coconut oil (which is nearly half lauric acid) was similarly inconclusive about the effects on cardiovascular disease incidence.
Further reading
- Berner, Louise A. (1993). Defining the Role of Milkfat in Balanced Diets. In John E. Kinsella (Ed.) Advances in Food and Nutrition Research – Volume 37. Academic Press. pp. 159–166. ISBN 978-0-12-016437-0.
- Kabara, Jon J. (1978). The Pharmacological Effect of Lipids. Champaign IL: American Oil Chemist's Society. ISBN 9991817697.
- Kabara, Jon J. (2008). Fats Are Good for You and Other Secrets – How Saturated Fat and Cholesterol Actually Benefit the Body. North Atlantic Books. ISBN 1-55643-690-4.
External links
Types of lipids
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General | |
Geometry | |
Eicosanoids | |
Fatty acids | |
Glycerides | |
Phospholipids | |
Sphingolipids | |
Steroids |
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