
%0 Journal Article
%A Smith, Graham 
%A Kennard, Colin H. L. 
%T The Crystal and Molecular Structure of the 1:1 Adduct Hydrate of Pyrazine-2,3-dicarboxylic Acid with 1,1-Diethylurea
%J Australian Journal of Chemistry
%D 2001/05/11
%V 53
%N 12
%P 999-1001
%K X-ray crystal structure; diethylurea; carboxylic acids; pyrazines.
%R https://doi.org/10.1071/CH00150
%U https://www.publish.csiro.au/paper/CH00150 
%X The adduct hydrate of 1,1-diethylurea with pyrazine-2,3-dicarboxylic acid, &#91;(C6H4N2O4)(C5H12N2O)&#93;.H2O has been prepared and characterized using low-temperature single-crystal X-ray diffraction methods. A primary asymmetric cyclic hydrogen-bonding interaction, similar to those found in other adducts of 1,1-diethylurea with the nitro-substituted aromatic acids, was found between the amide group of the substituted urea and one carboxylic acid group of the acid. Further peripheral hydrogen-bonding associations involving both the f irst and the second carboxylic acid groups, urea and the lattice water molecule result in a ribbon polymer structure. 
