Hemicucurbituril

This compound closely resembles cucurbituril cut in half along the equator and the chemistry is also similar.

The success of the reaction critically depends on the acid concentration, which is why the discovery of the compound took until 2004.

A crystalline product settles out of the solution which is the inclusion compound of Hemicucurbituril with water or HCl.

These guests can be driven out by application of elevated temperature and a vacuum.

With tweaking of the reaction conditions the hemicucurbit[12]uril (n = 6) is also obtained.