Ethyl 3-oxohexanoate → HCID 178439508, compound

Participants

Reaction Steps

To a solution of 2-chloro-3-nitrobenzoic acid (5.0 g) in THF (50 ml) was added borane-tetrahydrofuran complex (1M THF solution, 30 ml) under ice-cooling and the mixture was stirred at room temperature for 24 hours. To the reaction mixture was added a saturated aqueous sodium hydrogencarbonate solution and the mixture was extracted with ethyl acetate. The extract was washed with water and a saturated aqueous sodium chloride solution, and dried over anhydrous magnesium sulfate. The solvent was evaporated to give a pale-yellow solid (3.7 g). The obtained pale-yellow solid (1.6. g) and manganese dioxide (1.7 g) were heated under reflux in toluene for 4.5 hours. The insoluble material was filtered off and the filtrate was concentrated under reduced pressure. The obtained residue was purified by silica gel column chromatography (eluent:hexane-ethyl acetate (4:1)) to give 2-chloro-3-nitrobenzaldehyde (1.3 g) as a pale-yellow solid. Subsequently, the title compound was prepared from 2-chloro-3-nitrobenzaldehyde, 3-aminopyrazole and ethyl 3-ketohexanoate in the same manner as in Example 25.

Provenance & Evidence