Org. Synth. 1938, 18, 33
[Acetic acid, benzoyl-, ethyl ester]
Submitted by R. L. Shriner, A. G. Schmidt, and L. J. Roll.
Checked by C. R. Noller and I. Bergsteinsson.
) Preparation of Ethyl Benzoylacetoacetate
.—In a 5-l. three-necked flask
, fitted with a liquid-sealed mechanical stirrer
and a reflux condenser
, are placed 3.4 l. of dry benzene (Note 1)
, 195 g. (1.5 moles) of ethyl acetoacetate (Org. Syn. Coll. Vol. I, 1941, 235)
, and 34.5 g. (1.5 gram atoms) of clean sodium
. The mixture is heated on a steam cone
with stirring and allowed to reflux gently for twenty-four hours. After the suspension of the sodioacetoacetic ester
has been cooled slightly, 263 g. (218 cc., 1.9 moles) of benzoyl chloride
is added over a period of three hours. The mixture is refluxed with stirring for an additional eight hours. It is then cooled to room temperature, and 375 g. of cracked ice is added. After thorough shaking, the benzene
layer, which contains the ethyl benzoylacetoacetate
, is separated, washed with 75 cc. of 5 per cent sodium bicarbonate
solution, dried with sodium sulfate
, and the benzene
distilled (Note 2)
. The residue is distilled in vacuo
from a 500-cc. Claisen flask with a 50-cm. fractionating side arm
. After a small fore-run of benzoyl chloride
, the fraction boiling at 142–148°/6 mm.
, or 177–181°/20 mm.
, is collected. The yield is 223–263 g.
per cent of the theoretical amount).
(B) Hydrolysis of Ethyl Benzoylacetoacetate.—Thirty-two grams (0.6 mole) of ammonium chloride is dissolved in 150 cc. (8.3 moles) of water in a 500-cc. Erlenmeyer flask, and 10 cc. (0.15 mole) of ammonia (sp. gr. 0.9) is added. The solution is warmed to 42°, 58.5 g. (0.25 mole) of ethyl benzoylacetoacetate at 20° is added quickly, and the mixture is shaken (Note 3). The flask is placed in a water bath at 42° for exactly ten minutes and then cooled rapidly by placing it in an ice bath. The solution is extracted twice with 100-cc. portions of ether, and the ether solution is dried with anhydrous magnesium sulfate. The ether is distilled, and the residue distilled in vacuo; the yield is 37.0–37.5 g. (77–78 per cent of the theoretical amount) of ethyl benzoylacetate boiling at 132–137°/4 mm., or 165–169°/20 mm.
was dried by distillation, the first portion of the distillate being discarded.
It is essential that these steps in the isolation be carried through as rapidly as possible.
Larger amounts gave lower yields. The exact procedure must be followed as to time, temperature, and amounts of reagents, and the procedure must be completed without interruption.
has been prepared by the condensation (by means of sodium ethoxide
) of ethyl acetate
with ethyl benzoate
with ethyl carbonate
with ethyl oxalate
, with subsequent heating;3
by treatment of ethyl phenylpropiolate4
or α-bromocinnamic acid5
with concentrated sulfuric acid
, and of ethyl diazoacetate
by the condensation of benzene
with the monoethyl ester of malonyl monoacid chloride and aluminum chloride
of benzoyl chloride
with the product of the reaction of magnesium
and ethyl chloroacetate in ether
by the action of alcohol on benzoylacetimino ethyl ether hydrochloride
and by the hydrolysis of ethyl benzoylacetoacetate
This preparation is referenced from:
Chemical Abstracts Nomenclature (Collective Index Number);
monoethyl ester of malonyl monoacid chloride
sulfuric acid (7664-93-9)
ethyl acetate (141-78-6)
ammonium chloride (12125-02-9)
sodium bicarbonate (144-55-8)
sodium sulfate (7757-82-6)
benzoyl chloride (98-88-4)
aluminum chloride (3495-54-3)
sodium ethoxide (141-52-6)
Ethyl chloroacetate (105-39-5)
ethyl benzoate (93-89-0)
Ethyl acetoacetate (141-97-9)
magnesium sulfate (7487-88-9)
Acetic acid, benzoyl-, ethyl ester (94-02-0)
Ethyl benzoylacetoacetate (569-37-9)
ethyl phenylpropiolate (2216-94-6)
ethyl diazoacetate (623-73-4)
benzoylacetimino ethyl ether hydrochloride
Copyright © 1921-, Organic Syntheses, Inc. All Rights Reserved