1679-53-4

Crystals. Melting point 75.5-76.5℃.

Reactant involved in: • ;Synthesis of copolymers of acrylamide and sodium acryloyloxydecanoate1• ;Macrolactonization for preparation of Sansalvamide A2• ;Studies of chain length selectivity for cutinase catalyzed polycondensation reactions3• ;Ruthenium-catalyzed esterification followed by macrocyclization4• ;Synthesis of anhydrides and esters5

ChEBI: A 10-carbon, omega-hydroxy fatty acid, shown to be the preferred hydroxylation product (together with the 9-OH isomer) of capric acid in biosystems, and used as a standard in lipid assays; reported to have cytotoxic effects.

The alkaline cleavage of ricinoleates may be carried out in ethanol at temperatures of 190-200℃ using two to three equivalents of NaOH to give yields up to 69% of pure 10-hydroxydecanoic acid. This method avoids the use of large excesses of alkali as well as the use of high boiling alcohols as reaction media.
 In a typical experiment we placed 46.8 g (150 mmoles) of methyl ricinoleate and a solution of 12.0 g (300 mmoles) of NaOH in 100 ml of 95% ethanol. The autoclave was placed in an oven at 190-200℃ for 16-18 hr and then cooled to room temperature, vented to remove a certain amount of ethylene (identified by its mass spectrum) produced during heating and opened. After dissolving the semisolid contents in about 500 ml of water, the resulting solution was extracted with three 200 ml portions of ether to remove neutral material. This step may be omitted if it is not desired to retain the 2-octanol formed as coproduct. The aqueous phase was then acidified with 30 ml of concentrated hydrochloric acid, and the liberated acids extracted with two 200 ml portions of ether. After drying over magnesium sulfate and evaporation under reduced pressure to give about 35 g of solid, the crude acids were then dissolved in 100 ml of warm ethyl acetate and 100 ml of heptane was added. After standing overnight at 0℃ the mixture deposited 20.2 g of crystals, mp 71.5-74.5℃ which on recrystallization from benzene, 140 ml, yielded 19.4 g (104 mmoles, 69%) of 10-hydroxydecanoic acid, mp 73-75℃ (lit. 75-76℃). The above conditions are optimal when methyl ricinoleate is utilized, but the cleavage will proceed at lower temperatures. At 160 C about 41% yield of product was obtained after approximately the same reaction time.^[1]

[1] CARL A. ELLIGER   M. J D. A convenient preparation of 10-hydroxydecanoic acid[J]. Journal of the American Oil Chemists Society, 1972, 49 4: 278. DOI:10.1007/BF02582593.