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ChemicalBook CAS DataBase List n-Docosanol
661-19-8

n-Docosanol synthesis

10synthesis methods
-

Yield:661-19-8 87.6%

Reaction Conditions:

with sodium tetrahydroborate;iodine in tetrahydrofuran at 0 - 30;Reagent/catalyst;

Steps:

2; 3 PREPARATION OF DOCOSANOL:

Sodium borohydride (2.9 g) was suspended in THF (100 ml) at 20-30 °C and cooled to 0-5 °C. Thereafter, added a solution of iodine (7.5 g) dissolved in THF (30 ml) over a period of 1-2 h at 0-5 °C followed by a solution of docosanoic acid (20 g) dissolved in THF (140 ml) in 30-40 min. The reaction mixture was stirred for 2-4 h at 20-30 °C. After completion of reaction, the reaction mixture was carefully quenched with dil. HC1 (30 ml, 3N) at 20-30 °C and evaporated the solvent under reduced pressure (40-50 mm Hg) at 40-45 °C to get a turbid oily mass. To the above residue DM water (200 ml) was added and extracted the product in methyl-tert-butyl ether (300 ml). The organic extract was washed with an aqueous solution of 10% w/w sodium hydroxide (100 ml), an aqueous solution of 5% w/w sodium metabisulfite and finally with DM water (100 ml). Thereafter, the organic extract was concentrated under reduced pressure (20-40 mm Hg) at 40-50 °C to get a white colour residue. The above residue was dissolved in n- heptane (100 ml) at 40-45 °C and stirred for an hour at 20-25 °C. The resulting solid was filtered and dried under reduced pressure (10-20 mm Hg) to afford 16.8 g of the title compound. Yield: 87.6 % of theory Chromatographic purity (by GC): >98 %

References:

WO2018/220504,2018,A1 Location in patent:Page/Page column 8; 9

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