Diaminotriazine substituted 1,3-alternate calix[4]arenes

Abstract

The synthesis and crystal structures of two calix[4]arenes adopting the 1,3-alternate conformation substituted at the wide rim with diaminotriazine moieties are described. The crystal structure of the disubstituted calixarene 8 is governed by the diaminotriazine moieties which form infinite bands through hydrogen bonding. Around the diaminotriazine bands the calix[4]arene backbones are placed. In contrast hydrogen bonding between the diaminotriazine moieties of the tetrasubstituted calixarene 9 favour face to face complexes resulting in infinite strands. Hydrogen bonds in both compounds 8 and 9 are broken by polar solvents as the ¹H NMR spectra in DMSO-d₆ indicates.