Structural insight into the anion–water cluster: stabilised by alcohol and carboxylic acid containing tripodal ligand

2014-05-16T14:58:28Z (GMT) by Md. Najbul Hoque Arghya Basu Gopal Das
<div><p>A new flexible N-bridged, unsymmetrical, water-soluble tripodal ligand (<b>L</b>) bearing alcohol and carboxylic acid groups has been synthesised and its solid-state interaction with anions has been investigated. The fully deprotonated ligand encapsulates a sodium cation in a half cryptand bowl-shaped cavity (<b>1</b>). The chloride complex <b>2</b>, contains a cyclohexane-like water cluster incorporating ligand OH groups. However, complexes with bromide and nitrate (<b>3</b> and <b>4</b>) are dimeric. Tetrahedral clusters containing two water molecules and two anions were found in complexes <b>3</b> and <b>4</b>. Perchlorate complex <b>5</b> forms perchlorate–methanol adducts. Complex <b>1</b> forms a hydrophilic cation–water channel and complexes <b>2</b>–<b>4</b> form anion–water channels between the hydrophobic layers of the naphthalene moieties. Complexes <b>2</b>, <b>5</b> and <b>3</b>, <b>4</b> are isostructural in nature having similar packing structures.</p></div>