Water → Allysine ethylene acetal

Participants

Reaction Steps

A 250 ml flask equipped with an argon inlet, magnetic stir bar and reflux condenser was charged with 5.9 g of the product from Example 1 and water (80 ml). The reaction was refluxed for seven hours and then allowed to stir overnight at room temperature. The reaction mixture was diluted with water (120 ml) and washed with methylene chloride (2×50 ml). The combined methylene chloride layers were extracted once with water (50 ml), and the combined aqueous layers were concentrated in vacuo. The residue was concentrated in vacuo from 100% ethanol (2×100 ml) to a solid. The solid was dissolved in water (15 ml) and the solution was stirred with a magnetic stir bar as 100% ethanol (150 ml) was added in a slow stream. Stirring was stopped, and the mixture was allowed to stand for one hour and then filtered. The solids were washed with 100% ethanol (2×25 ml), air-dried for 15 minutes, and then volatiles were removed under high vacuum overnight to give 2.0 g of the desired product as a white powder; m.p. 224-226°(decomp.).

Provenance & Evidence