Water → HCID 12397765, compound

Diethyl 3,4-dihydronaphthalene-1,1 (2H)-dicarboxylate (see J. Org. Chem., 54, 2713-18 (1989)) (5.129 g, 18.56 mmol), sodium chloride (2.17 g, 37.1 mmol) and water (1 ml) were heated in dimethyl sulfoxide (10 ml) at 180° C. for 1.5 days. After cooling to room temperature, water was added, and the mixture was extracted twice with ethyl acetate. The collected organic layer was dried over anhydrous magnesium sulfate. The solvent was evaporated under reduced pressure and the obtained residue was purified by silica gel column chromatography (hexane/ethyl acetate=15/1) to give a crude product of ethyl 1,2,3,4-tetrahydronaphthalene-1-carboxylate as a yellow liquid. To a solution of the obtained liquid in methanol (20 ml)-tetrahydrofuran (10 ml) was added 1N aqueous sodium hydroxide solution (30 ml, 30 mmol), and the mixture was stirred overnight at room temperature. The reaction solution was concentrated, diluted with water, and washed with diethyl ether. The obtained aqueous solution was acidified with 1N hydrochloric acid and extracted twice with diethyl ether. The collected organic layer was dried over anhydrous magnesium sulfate. The solvent was evaporated under reduced pressure and the obtained residue was crystallized from diethyl ether-hexane to give the objective substance.

1. extractionthe mixture was extracted twice with ethyl acetate
2. dry with materialThe collected organic layer was dried over anhydrous magnesium sulfate
3. customThe solvent was evaporated under reduced pressure
4. customthe obtained residue was purified by silica gel column chromatography (hexane/ethyl acetate=15/1)

ORD record

ord-516b9820cc8d47d7bfe10003f80c5729

Source dataset

uspto-grants-2006_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06982348B2