Hydrogen bonding in the perhydrate and hydrates of 1,4-diazabicyclo[2.2.2]octane (DABCO)

The crystal structures of the bis(perhydrate), the monohydrate, and the hexahydrate of 1,4-diazabicyclo[2.2.2]octane (DABCO) were determined by single-crystal X-ray diffraction to investigate the hydrogen bonding architectures. The bis(perhydrate) revealed helical chains of hydrogen peroxide molecules forming a 3-D network by interaction with the diamine. In the monohydrate, water and diamine molecules are alternately linked. In the hexahydrate, cyclic water aggregates create cavities which are occupied by DABCO molecules doubly hydrogen-bonded to the water framework of the cage.