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ChemicalBook CAS DataBase List Catechol
120-80-9

Catechol synthesis

14synthesis methods
Pyrocatechol may be obtained by the fusion of o-phenolsulfonic acid with alkali, by heating chorophenol with a solution of sodium hydroxide at 200°C in an autoclave, or by cleavage of the methyl ether group of guaiacol (obtained from beechwood tar) with hydriodic acid.
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Yield:120-80-9 99%

Reaction Conditions:

Stage #1: 2-methoxy-phenolwith pyridine;iodine;aluminium in acetonitrile; for 18 h;Reflux;
Stage #2: with hydrogenchloride in lithium hydroxide monohydrate;acetonitrile at 20;

Steps:

14 Example 14 (guaiacol demethylation)

To a 100 ml eggplant flask were added iodine (2.098 g), aluminum powder (0.467 g) and acetonitrile (50 ml), heated toReflux, stir for 2 hours to the purple red of iodine disappears. Then pyridine (1.889 g) and guaiacol (0.621 g) were added to continue the reaction18 hours. After stirring at room temperature, 2 mol / L dilute hydrochloric acid (10 ml) was added to the reaction solution, and the mixture was extracted with ethyl acetate(50 ml x 3). The organic phases were combined and dried over anhydrous sodium sulfate. The filtrate was evaporated to dryness with a rotary evaporator and the residue passed throughPurified column chromatography (mobile phase ethyl acetate: petroleum ether = 1: 1, volume ratio) to obtain catechol (colorless needleCrystal, 0.546 g, yield 99%).

References:

CN106278825,2017,A Location in patent:Paragraph 0077; 0078; 0079

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