Diethyl aminomalonate hydrochloride

DIETHYL AMINOMALONATE HYDROCHLORIDE (Malonic acid, amino-, diethyl ester, hydrochloride)... 

B. Diethyl aminomalonate hydrochloride. The crude diethyl aminomalonate is diluted with 80 ml. of dry ether and filtered to remove a small amount of white solid. The filtrate is collected in a 250-ml. Erlenmeyer flask and cooled in an ice bath. Dry hydrogen chloride is passed just over the solution while it is being stirred mechanically (Note 6). The fine white crystals which precipitate are collected by suction filtration and washed three times with a total of 60 ml. of dry ether (Note 7). The filtrate and washings are treated again with hydrogen chloride, and a second crop of diethyl aminomalonate hydrochloride is collected and washed as before. This process is repeated until no further precipitation results from passing hydrogen chloride into the solution. A total of 16.5-17.4 g. (78-82% yield based on diethyl malonate) of diethyl aminomalonate hydrochloride, m.p. 162-163°, is obtained. Recrystallization from alcohol-ether affords a purer product, 164-165°. 

The benzodiazepine derivative 246 was synthesized (yield 49%) by heating 6,8-dibromoisatoic anhydride with diethyl aminomalonate hydrochloride in the presence of triethylamine [160],... 

Shaprio described a nonoxidative method for preparing 2-substituted 4-ox-azolecarboxylic acid esters 591 (Scheme 1.161). He prepared the key intermediate, dimethyl amino[(phenylthio)methyl]malonate 588, in three straightforward steps from diethyl aminomalonate hydrochloride. Acylation of 588 gave the A-acyl derivative 589 in excellent yield, which was sequentially chlorinated and cyclized in one pot to afford the 2,4,4,5-tetrasubstituted oxazoline 590. The author noted that anhydrous conditions were required to minimize sulfoxide formation. This was the only product isolated if the chlorination cyclization sequence was carried out in a hydroxylic solvent. 

Diethyl aminomalonate, from reduction of diethyl isonitrosomalonate, 24 reaction with hydrogen chloride to form diethyl aminomalonate hydrochloride, 25... 

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