Glutaric acid monoamide

In a 500-ml. three-necked flask fitted with a sealed mechanical stirrer and a reflux condenser are placed 86 g. (1 mole) of 7-butyrolactone (Note 1) and 72 g. (1.1 moles) of potassium cyanide (Note 2). As the contents of the flask are stirred, the mixture is heated in an oil bath for 2 hours at a temperature of 190-195° (Note 3). There is an initial vigorous reaction which soon subsides. After the completion of the heating period the mixture is cooled to about 100°, and the potassium salt of the cyano acid is dissolved in about 200 ml. of hot water. The warm solution is cautiously acidified to Congo Red by the addition of about 90 ml. of concentrated hydrochloric acid. The resultant solution, which contains glutaric acid monoamide and potassium chloride, is used to prepare glutaric acid or glutarimide. 

In a later procedure, y-butyrolactone is heated with potassium cyanide at 190- 195° for 2 hrs., water is added to dissolve the potassium salt of the cyano acid, and the warm solution is treated with enough hydrochloric acid to liberate the free carboxyl group and to effect partial hydrolysis to give glutaric acid monoamide. 

In a related procedure, thermal cyclization of 7V-(phenylethyl)glutaric acid monoamide (306) affords benzo[a]quinolizidines (307). An isomer of (306), in the presence of methyl iodide, gave compounds (308) through two successive alkylations <82H(17)263>. Related emetine precursors (309) were similarly obtained (Scheme 68) <90JCS(P1)1469>. 

ETHYL-3-METHYL, 36, 28 Glutaric acid monoamide, 37, 47 Glutaric anhydride, 3-methyl, 38,52 a-PHENYL, 30, 81 Glutarimide, 37, 47 Glycerol, 32, 72... 

Glutaric Acid. To the solution of monoamide is added 200 ml. of concentrated hydrochloric acid, and the mixture is heated under reflux in the hood for 1 hour. The reaction mixture is evaporated to... 

Monoesters of symmetric dicarboxylic acids can be prepared either by monoesterification of a diacid [1] or by monosaponification of a diester. Dicarboxylic acids which can form five- or six-membered cyclic anhydrides are readily transformed into monoesters via these intermediates, but for diacids which cannot be converted into such cyclic anhydrides monosaponification of diesters seems to be more reliable than selective monoesterification. Monoesters or monoamides of succinic, maleic, glutaric, or related diacids can be rather unstable, because of the dose proximity of a carboxyl group (see Section 3.3). 

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