ChemicalBook CAS DataBase List 5,8-Dihydroxy-1,4-naphthoquinone

5,8-Dihydroxy-1,4-naphthoquinone synthesis

13synthesis methods

Product Name:5,8-Dihydroxy-1,4-naphthoquinone
CAS Number:475-38-7
Molecular formula:C10H6O4
Molecular Weight:190.15

1,8-Dinitronaphthalene and 1,5-Dinitronaphthalene mixture or both alone and one of sulfur 40% fuming sulfuric ACID reaction, the product (5, 8 – dihydroxy – naphthoquinone) into Sulfurous acid?hydrogen salt.

108-31-6 Synthesis

108-31-6
823 suppliers
$13.47/50 G

123-31-9 Synthesis

123-31-9
812 suppliers
$13.00/25g

475-38-7
130 suppliers
$65.00/250 mg

Yield: 16.95%

Reaction Conditions:

with aluminum (III) chloride;sodium chloride at 200; for 2 h;High pressure;Friedel-Crafts Acylation;Temperature;

Steps:

1 Example 1 The method for the synthesis of naphthoquinone by molten salt method is as follows:
In the first step, the oven will be preheated to 160°C.Weigh the sample with 25% fullness of the hydrothermal reactor, including NaCl 2.10g, with a balance.Anhydrous AlCl 310.67g, maleic anhydride 1.18g and hydroquinone 1.10g;The weighed sample is placed in a grinding crucible, fully mixed, ground, and transferred to a hydrothermal reactor.The reaction vessel was screwed; the reaction vessel was placed in an oven that had been preheated to 200 DEG C. and subjected to Friedel-Crafts acylation reaction for 2 hours.After the reaction is complete, remove the reactor and allow the reactor vessel to cool to room temperature.A purple-black solid was obtained as a complex of 5,8-dihydroxy-1,4-naphthoquinone and tri-alumina;In the second step, transfer the purple-red solid obtained in the first step to a beaker.Add 20% hydrochloric acid solution to fully boil until bubbles are no longer generated, then filter to remove the upper solid;The solid was then dispersed with a small amount of ultrapure water and extracted three times with CH2Cl2.The resulting extract was dried under reduced pressure and dried in a vacuum oven under vacuum at 55°C for about 8 hours.0.3223 g of purple-red powder was obtained, namely naphthoquinone (5,8-dihydroxy-1,4-naphthoquinone).The theoretical yield of hydroquinone was 1.8998 g as the starting material, so the total yield was 16.95%.

References:

Yunnan China National Tobacco Industry Co., Ltd.;Hubei University;Chang Gang;Zhou Yang;Zhu Ruizhi;Liu Zhihua;Cao Yunbin;Cao Ribing CN107417508, 2017, A Location in patent:Paragraph 0028-0031; 0033-0042