反应详情

A solution of magnesium valproate in absolute ethanol was obtained in the following manner. To a magnetically stirred, clear, colorless solution of valproic acid (3.17 g; 0.022 mol; Sigma Aldrich Chemical Co.) in 25 mL of absolute ethanol was added 1.14 g (0.01 mol) of magnesium ethoxide solid; residual solid was rinsed in with 1 mL of absolute ethanol. Within 60 minutes, a clear, pale yellow solution was obtained; no heating was observed. One milliliter portions of the solution were aliquoted into test tubes, and a second solvent or solution was added in portions. The results of the additions are summarized in Table 2. A 15 mL portion of acetonitrile was added to an equal volume of the ethanol solution of magnesium valproate. A white precipitate formed, which was isolated by filtration, washed with a fresh portion of acetonitrile, and dried to constant mass. The product, magnesium valproate hydrate, was obtained in 89% yield as a white solid, which exhibited an elemental composition identical to that calculated for magnesium valproate hydrate. The product did not melt at temperatures as high as 300° C. The product was not hygroscopic or deliquescent. The theoretical valproate content (weight %) of magnesium valproate hydrate is 88.6%; the valproate content found by HPLC analysis was 88.5%.

1. washresidual solid was rinsed in with 1 mL of absolute ethanol
2. customa clear, pale yellow solution was obtained
3. additiona second solvent or solution was added in portions
4. customThe results of the additions
5. customA white precipitate formed
6. customwhich was isolated by filtration
7. washwashed with a fresh portion of acetonitrile
8. customdried to constant mass