Synthesis of Glycoluril Analogues by an Improved Weiss–Cook Condensation Reaction

ABSTRACT A series of glycoluril analogues (GA) have been synthesized by an improved Weiss–Cook condensation reaction. The structure of GA has been determined by single crystal X‐ray diffraction technique, and the results show that there is only one enantiomer or diastereomer in these crystals. Based on the structural characteristics, this paper speculates on the possible reaction mechanism and tries to explain that such a one‐step reaction is completely reasonable to generate only one enantiomer or diastereomer. Therefore, this method provides a simple route for the synthesis of chiral GA. Most importantly, this work also provides a chiral basic structural unit of cucurbituril or unclosed cucurbituril and lays a material foundation for the synthesis of novel unclosed cucurbituril or cucurbit[n]urils.