4- Aminotriazole. carboxylation

Aminotriazole carboxylic AcidsyC,H4N4Oj, mw 128.09, N 43.74%. The following isomers and some derivatives are described in the literature ... 

Aminotriazole is carboxylated at the 5-position by heating with aqueous sodium bicarbonate in a Kolbe-type reaction (7lJCS(C)l50l). 2-Thiazolinones undergo the Gatter-mann and Reimer-Tiemann reactions at the 4-position, and 3- and 4-pyrazolinone anions on alkylation give 4-alkyl as well as O- and N-alkyl derivatives. 

Imine formation via condensation of aminotriazole 260 with l-methyl-4,5-dioxopyrrolidine-3-carboxylic acid methyl ester 259 leads to formation of the linear tricyclic system 261 under base-mediated conditions (Equation 71) <1997PHA276>. 

Carboxylation of C-lithio or Grignard derivatives of triazoles gives the corresponding carboxylic acids. 4-Aminotriazole has been car-boxylated at the 5-position (14%) by heating with aqueous sodium bicarbonate. ... 

Some acid-catalyzed decarboxylations are recorded. 4-Aminotriazole-5-carboxylic acid, refluxed in dilute hydrochloric acid, gave 5-aminotriazole hydrochloride (1 hr, 57%) 4-amino-3-cyclohexyltriazole-5-carboxylic acid similarly gave 4-amino-3-cyclohexyltriazole (1 hr, 63%) [71JCS(C)1501]. 

The esters of 4-aminotriazole-5-carboxylic acids have been little explored. Ethyl 4-anilinotriazole-5-carboxylate and ethanolic potassium hydroxide furnished the corresponding acid (no details, 77%) (57JOC654). Ethyl... 

Several Curtius reactions have been employed to produce a primary amino group. Triazole-4-carboxylic acid [from acetylene-1-carboxylic acid and hydrazoic acid in chloroform (46% yield)] was esterified (70%), then converted to the hydrazide (71%) and on to the urethane (52%) and 4-aminotriazole (20%) (57YZ452). The final stage went better for 4-amino-5-methyltriazole, which achieved a 53% throughput from the urethane (76JHC589). 4-Amino-1 -methyltriazole was obtained in 64% yield from 4-ethoxycarbonyl-l-methyltriazole in this way (59ACS888). 

Aminotriazole-5-carboxylic acid (but not 84) was found to be incorporated into the RNA of tobacco mosiac virus and of E. coli, and it inhibited both organisms, whereas 84 was inert (57BJ323). 4-Anilino-5-ethoxycarbonyltriazoles, in which the benzene ring carries a m- or p-fluoro or chloro substituent, are claimed as anthelmintics (70GEP2009134). 5-Ethoxy-3-halophenyl-4-morpholino- or 4- -hydroxyethylamino triazoles are claimed... 

There is strong evidence that 5,6-didehydrobenzimidazoles (591) have been generated by both oxidation of the aminotriazoles (592) (Section II.l.D) and aprotic diazotization of the amino acid 593 (Section II.l.C). The intermediate diazonium carboxylate 594 from the latter precursor proved to be remarkably stable but finally gave a low yield of the tetracyclone adduct 595b upon thermolysis. Oxidation of (592) led to much better yields of the expected aryne... 

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