Org. Synth. 1931, 11, 1
DOI: 10.15227/orgsyn.011.0001
[Acrolein, diethyl acetal]
Submitted by E. J. Witzemann, Wm. Lloyd Evans, Henry Hass, and E. F. Schroeder.
Checked by Frank C. Whitmore and Harry T. Neher.
1. Procedure
To 340 g. (6 moles) of dry, powdered potassium hydroxide (Note 1) in a 500-cc. short-necked round-bottomed flask (Note 2) is added 167 g. (1 mole) of β-chloropropionaldehyde acetal (p. 137). The mixture is shaken vigorously and attached at once to a three-bulbed Glinsky or other suitable column, connected to a water condenser set for distillation (Note 3). The flask is heated in an oil bath at 210–220° until nothing more distils (Note 4). The distillate is transferred to a separatory funnel and the lower aqueous layer is removed. The acrolein acetal is dried over 10 g. of potassium carbonate, filtered, and distilled from a modified Claisen flask (Fig. 2). The yield is 98 g. (75 per cent of the theoretical amount) of a product which boils at 122–126°.
Fig. 2
Fig. 2
2. Notes
1. The powdered potassium hydroxide should pass a 60-mesh sieve (24 per cm.). The dryness of the powder is of the utmost importance. Water must be avoided as much as possible. Therefore, the potassium hydroxide should be fused at 350° for two hours and then pulverized as rapidly as possible. A 24-cm. (10-in.) disk pulverizer having a capacity of about 200 g. per minute is recommended. If the potassium hydroxide is not fused before pulverizing, the yield of acetal drops to about 60 per cent.
2. The concentrated potassium hydroxide left at the completion of the reaction attacks the glass rapidly. For this reason iron retorts made from 10-cm. (4-in.) pipe should be used when many runs are to be made.
3. The reaction between the acetal and the alkali is very vigorous.
4. A large low-boiling fraction indicates too much moisture in the potassium hydroxide used. See (Note 1).
3. Discussion
Acrolein acetal has been prepared by treatment of β-chloropropionaldehyde acetal with dry, powdered potassium hydroxide,1 and from acrolein, ethyl orthoformate, and ammonium nitrate in boiling alcohol.2
This preparation is referenced from:

References and Notes
  1. Wohl, Ber. 31, 1798 (1898); Witzemann, J. Am. Chem. Soc. 36, 1911 (1914); Spoehr and Young, Carnegie Inst. Washington Yearbook, 25, 176 (1925–1926); Expt. Sta. Record, 57, 817 (1927) [C. A. 22, 2368 (1928)].
  2. Fischer and Baer, Helv. Chim. Acta 18, 516 (1935).

Chemical Abstracts Nomenclature (Collective Index Number);
(Registry Number)

alcohol (64-17-5)

potassium carbonate (584-08-7)

Acrolein (107-02-8)

potassium hydroxide (1310-58-3)

ammonium nitrate

Ethyl orthoformate

Acrolein acetal

Acrolein, diethyl acetal

β-chloropropionaldehyde acetal (35573-93-4)