Monoethyl malonate → Ethyl 3-methoxy-4-methoxycarbonylbenzoylacetate

Participants

Reaction Steps

To a solution of ethyl hydrogen malonate (4.38 g, 33.2 mmol) in dry tetrahydrofuran (100 ml) cooled under an atmosphere of nitrogen to -60° C. with efficient stirring was added a solution of n-butyllithium in hexane (2.5M, 26.5 ml) rapidly dropwise, allowing the temperature to rise to -10° C. during the addition. After stirring the resulting suspension for 15 min at -10° C. it was recooled to -70° C. and a solution of 3-methoxy-4-methoxycarbonylbenzoyl chloride (4.46 g, 19.5 mmol) in dry tetrahydrofuran (30 ml) added dropwise. After addition, the reaction mixture was allowed to warm to room temperature and after 1 h diluted with cold aqueous hydrochloric acid (2M, 35 ml) and ice. The mixture was extracted with diethyl ether (200 ml) and the extract washed twice with a saturated solution of sodium bicarbonate, water and a saturated solution of sodium chloride. The organic layer was dried over magnesium sulphate, filtered and evaporated. The residue was purified on flash silica eluting with dichloromethane to give ethyl 3-methoxy-4-methoxycarbonylbenzoylacetate as an oil.

Provenance & Evidence