Diethyl Malonate → Diethyl 3-(benzyloxy)cyclobutane-1,1-dicarboxylate

Participants

Reaction Steps

To a stirred suspension of oil-free sodium hydride (10.7 g, 0.446 mol) in 270 ml of dry dioxane under nitrogen at room temperature was added over twenty minutes 69.1 g (0.432 mol) of diethyl malonate. After the addition, 1-chloro-2-benzyloxy-3-bromopropane (115 g, 0.437 mol) was added over 20 minutes, and the reaction was refluxed for 44 hours. The reaction was cooled to room temperature, and then a slurry of 10.7 g (0.446 mol) of oil-free sodium hydride in 100 ml of dioxane was cautiously added in portions. The mixture was refluxed for 120 hours and cooled to room temperature. The inorganics were removed by filtration, and the filtrate was concentrated in vacuo to an oil, which was partitioned between ether and water. The ether layer was dried (Na2SO4) and concentrated to an oil, which was distilled to give 58.8 g of desired product having a b.p. 142°-146°/0.3 mm.

Provenance & Evidence