1382748-79-9Relevant academic research and scientific papers
Urazole synthesis. Part 2: Facilitating N4 substitution
Chai, Weirui,Nguyen, Emily,Doran, Jennifer,Han, Katie,Weatherbie, Alexander,Fernandez, Daniel,Karimi, Sarah,Mynam, Ritwick,Humphrey, Caroline,Rana, Sara,Buynak, John D.
, p. 2308 - 2310 (2013)
The di-tert-butyl-di-p-nitrophenyl ester of hydrazinetetracarboxylic acid was prepared and shown to be useful in the preparation of urazoles (i.e., 1,2,4-triazolidine-3,5-diones), by reaction with a primary amine using either n-BuLi or pyridine as base, d
An efficient and general urazole synthesis
Chai, Weirui,Chang, Yuan,Buynak, John D.
, p. 3514 - 3517 (2012/08/14)
A general two-step scheme for the synthesis of N4 substituted urazoles (i.e., 1,2,4-triazolin-3,5-diones) is described. The first step involves the reaction of a primary amine with 2.5 equiv of phenyl chloroformate to produce diphenyl (N-substituted)imidodicarbonates. The second step involves the reaction of these compounds with hydrazine to produce N4 substituted urazoles. The mild reaction conditions permit synthesis of N4 oxygenated urazoles, not available via existing methodology. Bicyclic urazoles can be prepared through the subsequent reaction of these N4-protected urazoles with 2.5 equiv of NaH in DMF together with either 1,3-dibromopropane or 2-(tert-butyldimethylsilyloxy)-1,3- dibromopropane in the presence of NaI. The resultant bicyclic urazoles are observed to display varying degrees of pyrimidalization at N1 and N2, depending on substituents.
