Alkyl and diether bridged N,N,N′,N′-tetra(2-hydroxybenzyl)diamines: effects of hydrogen bonding on structure and solubility

Abstract

A solvent-free one-step method has been used to prepare two N,N,N′,N′-tetra(2-hydroxy-3,5-dimethylbenzyl)diaminoalkanes containing a long n-alkyl bridge (6 and 8 CH₂ groups between N-atoms). In addition, three novel N,N,N′,N′-tetra(2-hydroxy-5-alkyl-3-alkylbenzyl)-diaminoalkane-ethers (alkyl = methyl or t-butyl) have been prepared using the same method. The compounds were studied in the solid state using single crystal X-ray diffraction and their solubility was studied using UV/Vis spectroscopy. In the solid state, hydrogen bonding plays a key role in controlling the crystal packing and conformations of the molecules, thus affecting the solubility and properties of the compounds.