(1) Preparation of 2-tridecanone:
First, 2.3g of sodium metal was added to the reaction flask, and then 3mL of anhydrous ethanol was added, heated to 2530, and then 13.0g of ethyl acetoacetate, 10mL ethanol and 12.5mL of anhydrous ethyl ether were added dropwise to the solution, and stirred and refluxed for 1 hour; and then 21.85g of Lauryl chloride and 30 mL of ether were added to the reaction flask, and stirred and refluxed for 2-3 hours; after cooling, it was dissolved with dilute sulfuric acid, and the ether layer was separated, and the aqueous layer was extracted twice with ether, and the organic layers were combined and washed with distilled water, and the ether was recovered to obtain 15.7 g of intermediate 2-tridecanone in 92% yield.
(2) dodecanoyl acetaldehyde preparation:
With anhydrous ethanol as solvent, add 1.1g of sodium metal in the reaction vessel, heat and reflux for 1 hour, dropwise addition of 8g of 2-tridecanone, 3g of ethyl formate, stir the reaction for 4-6 hours, leave overnight, then washed with distilled water, and then extracted with ether for several times, the combined ether solution, dried with anhydrous sodium sulfate and filtered. After drying with anhydrous sodium sulfate and filtering, the ether was finally separated to obtain 8.3g of dodecanoyl acetaldehyde in 90.3% yield.
(3) a-hydroxy dodecanoyl ethyl sulfonate sodium preparation:
To the reaction vessel to add 60 ml of saturated sodium bisulfite saturated solution, and then slowly add 6.9 g of dodecanoyl acetaldehyde, 85 ~ 90 C. Reaction for 1.5 hours, cool down, filtration, washing, drying, a-hydroxy dodecanoyl ethyl sulfonate sodium 8.1g. Sodium a-hydroxydodecanoyl ethyl sulfonate 8.1g yield 89.3%, the content was 99.4% by HPLC.
