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ChemicalBook CAS DataBase List Ethyl 2,3-dihydrobenzo[b][1,4]dioxine-5-carboxylate
261767-10-6

Ethyl 2,3-dihydrobenzo[b][1,4]dioxine-5-carboxylate synthesis

2synthesis methods
-

Yield:261767-10-6 94%

Reaction Conditions:

with hydrogenchloride;sodium chloride;potassium carbonate in water;

Steps:

1 2,3-Dihydrobenzo[1,4]dioxin-5-carboxylic acid ethyl ester

A mixture of ethyl 2,3-dihydroxybenzoate (1000 g), tetra-n-butyl-ammonium bromide (880 g), potassium carbonate (1552 g), 1,2-dichloroethane (3216 g), and water (10 kg) was refluxed for 5 hours. The solution was cooled and extracted with toluene. The extract was washed with a solution of 1N hydrochloric acid and sodium chloride. The solution was partially concentrated and filtered through silica gel (300 g). The filtrated was concentrated to give the title compound (1074 g, 94%); m.p. 48-51° C.

References:

US6172062,2001,B2