Butylmalonic acid

Chemical Name butylpropanedioic acid mono-(1,2-diphenylhydrazide) Common Name Butylmalonic acid diphenylhydrazide Structural Formula ... 

The sec.-butylmalonic acid is extracted with three 200-cc. portions of ether, and the combined extracts are dried over calcium chloride overnight. The ether solution is then decanted into a 2-1. three-necked flask fitted with a mercury-sealed stirrer, reflux condenser, and dropping funnel. Five cubic centimeters of bromine is added at one time and the solution stirred until decolorized (Note 7). Then 50 cc. more bromine is added drop-wise at such a rate that the ether refluxes gently. When all the bromine has been added, 200 cc. of water is added through... 

Cognate preparations. Butylmalonic acid. This acid may be similarly prepared from diethyl butylmalonate (Expt 5.132) and melts at 102 °C after recrystallisation from benzene. 

Common Name Butylmalonic acid diphenylhydrazide Structural Formula ... 

Dicyclohexylcarbodiimide n-Butylmalonic acid ethyl ester Hydrazo benzene... 

The separate extracts are made acid to Congo paper with concentrated HCI, extracted with ethyl acetate, the extracts are washed neutral with a little water, dried and concentrated under vacuum. The colorless oil which remains is recrystallized twice from ether/petroleum ether, whereupon n-butylmalonic acid-N,N -diphenylhydrazide is obtained in the form of short needles which melt at 116°-118°C. 

A mixture comprising 108 g of phenyl hydrazine and 216 g of the diethyl ester of n-butylmalonic acid is heated on an oil bath at 170°-180°C for 12 hours. The residue is taken up with water in which an alkaline compound has been dissolved and acetic acid is added to precipitate 4-n-butyl-2-phenyl-pyrazolidine-3,5-dione. The product is a white crystalline solid having a MP 103°C. It is soluble in acetone and benzene, soluble in hot condition in methanol and ethanol and insoluble in water. 

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