1-Imidazolecarboxylic acid, esters

In most other reactions the azolecarboxylic acids and their derivatives behave as expected (cf. Scheme 52) (37CB2309), although some acid chlorides can be obtained only as hydrochlorides. Thus imidazolecarboxylic acids show the normal reactions they can be converted into hydrazides, acid halides, amides and esters, and reduced by lithium aluminum hydride to alcohols (70AHC(12)103). Again, thiazole- and isothiazole-carboxylic acid derivatives show the normal range of reactions. 

Imidazole-4-carboxylic acid, 5-methylamino-ethyl ester thermolysis, 4, 438 Imidazolecarboxylic acids decarboxylation, 5, 434—435 reactions, 5, 92, 434—435 Imidazolediazonium fluoroborates reactions, 5, 439 Imidazolediazonium salts reactions... 

Hydrolysis (especially with bromoacetic acid)28 of the dicarboxylic esters can be followed by decarboxylation and it is possible to remove one carboxyl group at a time to prepare the imidazole-4-carboxylic acid. The decarboxylation of imidazolecarboxylic acids has been discussed by Schipper and Day.2... 

Nonactivated esters are reduced only slowly if at all in strongly acidic medium at a lead cathode [45], whereas alkyl benzoates are reduced to a mixture of benzyl alcohol and alkyl benzyl ether [45,46], and alkyl 4-imidazolecarboxylates similarly are reduced to a mixture of the corresponding alcohol and ether [76]. Phenyl and benzyl benzoate give predominantly esters [23,34], as do also ethyl o-chloro- and m-bromobenzoate [46]. 

---