1,4-Benzodioxan-5-carboxylic acid

white to light yellow crystal powder

A solution of 2, 3-dihydrobenzo[b][l, 4]dioxine-5-carbaldehyde (0.500 g, 3.04 mmol) in acetone (10 mL) was stirred at 0-5°C and aqueous solution of sulphamic acid (0.455 g, 4.5 mmol) was added. The reaction mass was stirred for 20 min. Then aqueous solution of sodium chlorite (0.421 g, 4.5 mmol) was added and the reaction was further continued at RT for 18 h. After completion of reaction, reaction mixture was concentrated under reduced pressure and reaction mass was quenched with water. Solid obtained was filtered off and vacuum dried to afford 0.332 g of desired product. 1H NMR (DMSO-de): δ 4.27 (s, 4H), 6.84 (t, J = 7.2 Hz, 1H), 7.02 (d, J = 7.8 Hz, 1H), 7.20 (d, J= 7.5 Hz, 1H), 12.5 (bs, 1H); MS [M+H]Step A 5-Carboxy-2, 3-dihydro-1, 4-benzodioxin A mixture of 10.8 g (70 mmol) of 2, 3-dihydroxybenzoic acid, 38.6 g (280 mmol) of dry potassium carbonate and 24 ml (278 mmol) of 1, 2-dibromoethane in 40 ml of N, N-dimethylformamide is heated at 65° C. for 24 hours under an inert atmosphere. After cooling, the reaction mixture is diluted with water and then extracted with ether. The aqueous phase is then acidified with a 3N hydrochloric acid solution and subsequently extracted with dichloromethane. After removal of the solvent by evaporation in vacuo, the residue obtained is recrystallized from toluene to yield the title acid in the form of a white solid. Melting point 193-194° C.

Molecular Weight:180.16
XLogP3:1.2
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:4
Rotatable Bond Count:1
Exact Mass:180.04225873
Monoisotopic Mass:180.04225873
Topological Polar Surface Area:55.8
Heavy Atom Count:13
Complexity:204
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes