Synthesis and characterization of triazine-based compounds as potential precursors for hydrogen-bonded organic frameworks (HOFs)

Abstract

Crystalline porous materials have been recently recognized as useful and widely applicable industrial components for gas separation, adsorption and catalysis. Particularly important are the porous organic crystalline materials that utilize robust organic linkers for building self-organized stable frameworks. Hydrogen-bonded organic frameworks (HOFs) are an example of such supramolecular networks capable of self-assembling through hydrogen bonds into extended micro-porous systems. Several HOFs have been established and have proved to be putative candidates in the field of molecular storage and separation. Therefore, thorough research studies have been emanated in an attempt to discover novel HOFs with distinct characteristics. Thus, it is imperative to start with designing organic building blocks that may self-assemble into HOFs. Herein, we report the synthesis and characterization of mono-, di- and trisubstituted-1,3,5-triazines 13–20 endowed with uracil and-or thyminepropanehydrazide substituents 10 and 12 as potential synthons for the development of HOFs. This is achieved via the selective nucleophilic substitution reaction of cyanuric chloride 6 in the presence of thymine or uracilpropanehydrazides 10 and 12. The presence of the nucleic bases is expected to promote the self-recognition processes via hydrogen bonding; whereas, the integration of the s-triazine scaffold bearing these entities may induce non-covalent interactions that are crucial for the establishment of such dynamic systems.