Hydrochloric Acid → Ethyl 2-(3-methoxy-6,6-dimethyl-2-oxocyclohex-3-en-1-yl)-2-oxoacetate

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Reaction Steps

60% sodium hydride in mineral oil (2.41 g, 60.3 mmol) was suspended in anhydrous tetrahydrofuran (60 mL) under argon atmosphere and treated with a solution of 2-methoxy-5,5-dimethyl-cyclohex-2-enone (6.20 g, 40:2 mmol) in anhydrous tetrahydrofuran (50 mL). After 15 minutes, a solution of diethyl oxalate (8.17 mL, 60.3 mmol) in anhydrous tetrahydrofuran (50 mL) was added and the mixture was refluxed for 1 hour. The slurry was diluted with water (800 mL), acidified with 1N HCl (50 mL) and extracted with ethyl acetate (500 mL×2). The organic layers were collected, washed with brine, dried on Na2SO4 and evaporated to dryness to obtain the crude title compound (10.60 g) as an orange oil, which was used without further purification.

Provenance & Evidence