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ChemicalBook CAS DataBase List HEPES
7365-45-9

HEPES synthesis

5synthesis methods
-

Yield:7365-45-9 85.6%

Reaction Conditions:

Stage #1: 1-(2-hydroxyethyl)piperazine;sodium 2-hydroxyethanesulfonate in methanol at 50; for 5.5 h;
Stage #2: with 5percent by weight of raffinate in water;Solvent;Temperature;

Steps:

2; 5

0.5 mol of N-hydroxyethylpiperazine, 0.565 mol of sodium 2-hydroxyethanesulfonate and 500 mL of methanol were charged into a 1000 mL four-necked flask equipped with a reflux tube and subjected to a condensation reaction with sufficient stirring;First reacted at 50 for 2.5 hours, then gradually heated to reflux and continued to react for 3.0 hours;And then cooled to obtain a reaction mother liquor containing 4-hydroxyethylpiperazineethanesulfonate.The yield of sodium 4-hydroxyethylpiperazineethanesulfonate was calculated to be 93.6% by high performance liquid chromatography. 20 L of 4-hydroxyethylpiperazineethanesulfonate,Mass concentration of 15wt% raffinate, in the stirring effect,Diluted with deionized water to a concentration of 5 wt% by dialysis dialysis to remove sodium chloride,And finally concentrated by evaporation, cooling crystallization, filtration to get pure HEPES products,And finally washed once with anhydrous methanol, and dried by vacuum to obtain purified HEPES. The purified HEPES sample was formulated as a solution and then tested for purity:The purified HEPES sample was prepared as a solution and then tested for purity, 99.9%, yield 85.6%, pH = 6.46, Cl- concentration 6.8 μg / g.

References:

CN106905262,2017,A Location in patent:Paragraph 0034; 0035; 0047

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