Synthesis of conformationally diverse tetrathiacalix[4]arene(amido)crowns and tetrathiacalix[4]arene amides with pendant amine functions

A series of conformationally diverse novel tetrathiacalix4]arene(amido)crowns and amides from tetrakis((ethoxycarbonyl)methoxy)p-tert-butyl tetrathiacalix4]arene and its debutylated analog have been prepared by their reaction with diamines H₂N(CH₂)_nNH₂; n=2,3,4, and 6] and polyamines. It has been determined that the length of the alkyl spacer in diamines is pivotal for the formation of either the tetrathiacalix4]arene bis(amido)crowns or tetrathiacalix4]arene amides with pendant amine functions. The synthesized compounds represent potential building blocks for achieving sophisticated molecular assemblies for molecular organization and recognition. Single crystal X-ray analysis of tetrathiacalix4]arene bis(amido)crown 6a revealed that it has a 1,3-alternate conformation, which forms supramolecular complexes with chloroform.