Structure Optimization of Di-ionizable Calixarene Nano-baskets for Competitive Solvent Extraction of Alkali and Alkaline Earth Metals

Structure Optimization of Di-ionizable Calixarene Nano-baskets for Competitive Solvent Extraction of Alkali and Alkaline Earth Metals

The competitive solvent extractions of alkali and alkaline earth metals by di-ionizable calix[4]arene nano-baskets were studied using nine conformers of calix[4]arene nano-baskets. The objective of this work is to assess the variation of macrocycle conformation, orientation and position of pendant moieties upon the extraction parameters (efficiency, selectivity and $pH_{1/2}$) of the complexes. The results revealed that alternation of ring conformation in calixarene scaffold affects the solvent extraction parameters towards alkali and alkaline earth metals, while changing the orientation of pendant moieties from ortho- to para- as well as cis- to trans-analogues depicted no changes in those extraction parameters.