ChemicalBook CAS DataBase List 5,6-dihydroxy-1H-indole-2-carboxylic acid

5,6-dihydroxy-1H-indole-2-carboxylic acid synthesis

12synthesis methods

Product Name:5,6-dihydroxy-1H-indole-2-carboxylic acid
CAS Number:4790-08-3
Molecular formula:C9H7NO4
Molecular Weight:193.16

59-92-7 Synthesis

59-92-7
659 suppliers
$14.00/5g

5,6-dihydroxy-1H-indole-2-carboxylic acid

4790-08-3
71 suppliers
$117.00/100mg

Yield: 86%

Reaction Conditions:

with potassium hydrogencarbonate;sodium hydroxide;potassium hexacyanoferrate(III) in water for 0.25 h;Inert atmosphere;

Steps:

Synthesis of 5,6-dihydroxyindole-2-carboxylic acid (DHICA)1
DHICA was prepared under strictly anaerobic conditions. Firstly, DOPA (1g, 5.07 mmol) was dissolved in deionized water (500 mL) and the mixture was continuously stirred vigorously under a nitrogen atmosphere. Then a mixed solvent for K3[Fe(CN)6] (6.68 g, 20.3 mmol) and KHCO3 (2.54 g, 25.4 mmol) in H2O (60 mL) was gradually added to the above solution system, followed the NaOH (3 mol/L, 25 mL) was added to the solution. After stirring for15 min, the reaction was quenched by the addition of Na2S2O5 and the pH was adjusted to 3 with HCl (3 mol/L). After extraction with ethyl acetate (3×250 mL), the solution was then dried over anhydrous sodium sulphate. Finally, the solvent was evaporated under high vacuum to obtain the greyish powder (DHICA, 843 mg, 86% yield).

References:

Li, Zhan;Wang, Tianyou;Zhu, Fang;Wang, Zhao;Li, Yiwen [Chinese Chemical Letters,2020,vol. 31,# 3,p. 783 - 786] Location in patent:supporting information