Ethanol → 1,4,7-Trioxa-10-azacyclododecane

Participants

Reaction Steps

A quantity of the 1-benzyl-1-aza-4,7,10-trioxacyclododecane compound (3) prepared in Example 3 (45.1 g, 0.17 mol), ethanol (7 g), and 10% palladium on carbon (0.5 g) were shaken in hydrogen atmosphere at more than 50 psi (1 psi=6.9×103 Pa=0.07 kg cm-2). Hydrogen gas was recharged several times into the reaction chamber to keep the pressure elevated. Shaking was continued until the pressure lowering stopped (4 days). After the palladium carbon was filtered, the solvent was evaporated. The pure compound (4) was sublimed from the residue with gentle heating using a water bath (75°-77° C.; crude material melted at this temperature). The sublimate was white needles and was hygroscopic. Yield 60%; 1HNMR (D2O): δ 2.53-2.70 (t, 4H, N--CH2), 3.5-3.75 (m, 12H, O--CH2), no signal at 7.1 (Ar--H of benzyl group, possible contaminant).

Provenance & Evidence