38. Acetal

Nomenclature

CAS number: 105-57-7
1,1-Diethoxyethane; diethylacetal; acetaldehyde diethyl acetal; ethylidene diethyl ether.
C6H14O2; mol wt 118.17.
C 60.98%, H 11.94%, O 27.08%.

Description and references

Made from acetaldehyde and alcohol in the presence of anhydrous calcium chloride or of small quantities of mineral acid: H. Adkins, B. H. Nissen, J. Am. Chem. Soc. 44, 2750 (1922); eidem, Org. Synth. coll. vol. I, 1 (2nd ed., 1941). Toxicity study: H. F. Smyth et al., J. Ind. Hyg. Toxicol. 31, 60 (1949).

Chemical structure

Properties

Volatile liquid. Flammable. d420 0.8254. bp760 102.7°; bp200 66.3°; bp60 39.8°; bp40 31.9°; bp20 19.6°; bp10 8.0°; bp5 2.3°; bp1.0 23°. nD20 1.38193. Flash pt, closed cup: 97°F (36°C). uv spectrum: Purvis, J. Chem. Soc. 127, 9 (1925). 100 g water dissolve 5 g acetal. Misc with alcohol, 60% alcohol, ether. Sol in heptane, methylcyclohexane, propyl-, isopropyl-, butyl-, isobutyl alcohol, and ethyl acetate. Tends to polymerize on standing. Stable to alkalies. LD50 orally in rats: 4.57 g/kg (Smyth).

Use

Solvent; in synthetic perfumes such as jasmine; in organic syntheses.