Ethanol → Diethyl 2-(4-methylphenoxy)-3-oxobutanedioate

A sample of ethanol-free sodium ethoxide was prepared by dissolving sodium (3.0 g, 0.13 mole) in ethanol (50 ml) and then evaporating off the excess solvent. The last traces of ethanol were removed by the addition of dry toluene (50 ml), followed by evaporation to dryness. A stirred suspension of the white solid in dry ether (150 ml) under nitrogen, was treated dropwise with diethyl oxalate (17.6 ml, 0.13 mole) and the yellow solution allowed to stir for 21/2 hours at room temperature. A solution of the ethyl phenoxyacetate (0.13 mole, (D28)) in dry ether (50 ml) was added dropwise and the reaction mixture was left to stir overnight, before pouring into water (500 ml). The aqueous layer was separated, washed with ether (1×150 ml) and then acidified with dilute hydrochloric acid. The aqueous mixture was extracted with ether (3×150 ml) and the organic solution then washed with water (2×150 ml), dried (MgSO4) and evaporated to dryness to give the title compound as a yellow oil (28 g, 73%).

1. customevaporating off the excess solvent
2. customThe last traces of ethanol were removed by the addition of dry toluene (50 ml)
3. customfollowed by evaporation to dryness
4. additionA stirred suspension of the white solid in dry ether (150 ml) under nitrogen
5. waitthe reaction mixture was left
6. stirringto stir overnight
7. customThe aqueous layer was separated
8. washwashed with ether (1×150 ml)
9. extractionThe aqueous mixture was extracted with ether (3×150 ml)
10. washthe organic solution then washed with water (2×150 ml)
11. dry with materialdried (MgSO4)
12. customevaporated to dryness

ORD-Eintrag

ord-e11b2bfbbe224ca8be884b7e1e8f65f9

Quelldatensatz

uspto-grants-1985_10

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US04548948