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ChemicalBook CAS DataBase List Salidroside
10338-51-9

Salidroside synthesis

6synthesis methods
Ag2CO3 (4.11 kg, 15 mol) and molecular sieve powder (4A) (2.50 kg) were added to a stirred solution of 5 (2.70 kg, 15 mol) in CH2Cl2 (18 L). The resulting mixture was stirred for 15 min at ambient temperature, and a solution of 2,3,4,6-O-tetraacetyl-a -D-glucopyranosyl bromide 3 (6.60 kg, 15 mol) in CH2Cl2 (22 L) was added slowly over 40 min under vigorous stirring. The mixture was stirred for 16 h at room temperature. The reaction mixture was filtered, and the filtrate was washed with saturated NaHCO3 (5 L) and brine (5 L), dried over Na2SO4, and then concentrated to afford a syrup. n-Hexane (3.5 L) was slowly added to the syrupy residue under vigorous stirring. The precipitate formed was collected by filtration and dried in vacuo. The solid was dissolved in MeOH (30 L), and MeONa (1.23 kg, 22.5 mol) was added. The mixture was stirred at ambient temperature for about 24 h until TLC (n-hexane= MeOH 3=1) indicated that the material had disappeared. Concentrated HCl was added slowly to adjust the pH to 6–7. The organic layer was separated, dried (Na2SO4), filtered, and concentrated in vacuo. The residue was recrystallized twice from n-hexane=MeOH (5=1), giving 3.83 kg of white powder 1 (80% yield).[3]
Salidroside synthesis
-

Yield:10338-51-9 93%

Reaction Conditions:

with 5%-palladium/activated carbon;hydrogen in methanol at 20;Darkness;Green chemistry;

Steps:

15 Example 15 Preparation of 2-(4-hydroxyphenyl)ethyl-β-D-glucopyranoside (resorpirin)

1.1 g (2.8 mmol) of 1-O-(4-benzyloxy)-phenylethyl yl -β-D- glucopyranoside and 5% Pd / C 0.1 g of catalyst, and then repeatedly evacuated air charge of hydrogengas 3-5 times, and 20 mL of anhydrous methanol, protected from light, stirred at room temperature under a hydrogen atmosphere overnight.Filtration, concentration to dryness under reduced pressure,and recrystallized from ethanol to give 1-(4-hydroxy)-phenethyl-β-D-s-glucopyranoside as a white powder, which is aweight of 0.78 g. The yield was 93%.

References:

CN107880085,2018,A Location in patent:Paragraph 0039

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