Oxygen → 11-(Methylthio)undecanoic acid

Beteiligte Stoffe

Reaktionsschritte

Into a 3-neck round-bottom flask fitted with a condenser and an addition funnel were added 20 g of 11-mercaptoundecanoic acid, 13 g of methyl iodide and 200 mL of ethanol. A slow flow of nitrogen through the reactor was started to exclude oxygen because mercaptans can be converted into disulfides in the presence of air and strong alkali. A solution of 7.33 g of sodium hydroxide in 14.66 g of water was added dropwise to the reaction mixture via the addition funnel. Any unreacted methyl iodide, the ethanol and the water were removed using a rotovap. The residue was acidified using a mixture of concentrated hydrochloric acid and ice. After isolation the product was distilled. After a small amount of a low boiling fraction was collected, the crude product was collected at ~1 mm of Hg at 180° C. weighing 22.75 g. The crude product was distilled to yield 12.5 g of desired product representing 58.7% of theoretical based upon the weight of starting 11-mercaptoundecanoic acid.

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