9-Octadecenoic acid, 12-hydroxy-, (9Z,12S)- synthesis

Yield:84799-81-5 1.98 g

Reaction Conditions:

Stage #1: (Z)-(S)-12-hydroxyoctadec-9-enoic acid methyl esterwith methanol;potassium hydroxide in water; for 2 h;Reflux;
Stage #2: with hydrogenchloride in water;

Steps:

2.4. Hydrolysis of hydroxy ester S-1 to (S)-ricinoleic acid

A mixture of hydroxy ester S-1 (2 g), methanol (20 mL) and KOH(2.5 g) dissolved in water (10 mL) was refluxed for 2 h. Then methanol was distilled off (10 mL) and the mixture was acidified with concentrated hydrochloric acid (2.5 mL). The product was extracted with ethyl acetate (320 mL), washed with water(215 mL) and dried over anhydrous MgSO4. The solvent was evaporated to obtain (S)-ricinoleic acid (1.98 g, 100% pure by TLCand 1H NMR). [a]D =3.54 (c 2.89, CHCl3). IR (cm1, neat): 3337.3,2968.7, 2928.1, 2856.8, 1709.3, 1160.5, 1128.0, 950.5, 816.2. 1H NMR(CDCl3, d ppm): 6.20 (br.m, 1H), 5.52 (m, 1H), 5.40 (m, 1H), 3.62 (qn,J = 6.25 Hz, 1H), 2.33 (t, J = 7.40 Hz, 2H), 2.21 (t, J = 7.0 Hz, 2H), 2.03(m, 2H), 1.62 (m, 2H), 1.461.28 (m, 19H), 0.87 (t, J = 6.75 Hz, 3H).).13C NMR (CDCl3): 179.49 (s), 133.26 (d), 125.14 (d), 71.62 (d), 26.70(t), 36.22 (t), 34.01 (t), 31.79 (t), 29.47 (t), 29.30 (t), 28.98 (t,2CH2), 28.91 (t), 27.29 (t), 25.64 (t), 24.63 (t), 22.58 (t), 14.04 (q).

References:

Kula, Józef;Bonikowski, Radoslaw;Szewczyk, Malgorzata;Ciolak, Kornelia [Chemistry and Physics of Lipids,2014,vol. 183,p. 137 - 141]