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°. 

Methylimidazole HCI 2-Amino-5-chloro-2 -fluoro-benzophenone Ethyl aminomalonate hydrochloride... 

IB) 1-(2-Amino-5-chlorophenyl)-1-(2-fluorophenyl)-3,3-bis-(ethoxycarbonyl)-2-a2a-prop-1-ene A mixture of 88 g of the product obtained above, 300 g of ethyl aminomalonate hydrochloride and 60 ml of acetic acid in 2.3 liters of absolute ethanol is heated to the reflux temperature for 6 hours. The alcohol and the acetic acid are evaporated in vacuo and the residue is taken up in ether. The solution is washed with a dilute sodium bicarbonate solution and... 

A similar approach was described by Kim et al. <01MI1403> to build the Furstner synthon from the vinylogous amide 9, previously described, and the commercially available dimethyl aminomalonate hydrochloride as building block for pyrrole systems. The cyclocondensation reaction between the vinylogous amide 9 and dimethyl aminomalonate hydrochloride was performed in acetic acid at room temperature to yield the presumed Intermediate 12 via an acid-catalyzed nucleophilic substitution reaction. The mixture was then diluted with additional acetic acid and heated under reflux to facilitate the intramolecular ring closure and the loss of the methoxycarbonyl moiety to produce the desired pyrrole. Formation of lamellarin O dimethyl ether was achieved as in the Furstner approach <95JOC6637>. 

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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